Docs In Math Binder
PDF · 61 pages · 8.0 MB
Open PDF file
Compiled binder with a contents page dated 12.1.04 listing Phil's notes on math subjects: standard distributions (Gaussian, binomial, Poisson, Proakis excerpts), basic probability, the Levi-Civita symbol, stationary phase, selected integrals, asymptotic series, Gaussian quadrature, mean value theorems, the simplex method and Laplace methods for ODEs. It mixes handwritten notes with book Xerox pages and printed web pages. Handwritten parts are poorly read, so details are approximate.
AI-written summary; may contain errors. This description is approximate.
Extracted text (machine-read; may contain errors)
la a
eContents: 12.1.04
Mynotes onsome math subjects (some sections include book Xerox pages andweb pages)
1. Standard Distributions Section
Gaussian page, BinomiaV/Poisson notes +Proakis notes +Proakis Xerox(ProakishasBinomial,Gaussian,Chi-square, Rayleigh,Rice)+selfnotes
2.Basic Probability theory (web) +Balls inBins
v3.TheLevi-Civita Symbol
4.TheMethod ofStationary Phase (forevaluating integrals) +web
5.Selectedintegrals
Remainder Function, Mod ete
Gauss's lawlikeintegrals in8,6space.
6.MiseSinglepageitems[vtRem.55ANGE =04HiltsSpacejmulhiinkeqrale 5
7.Asymptotic Series (web)
e 8,GaussianQuadrature
9,Mean Value Theorems +web
10.ThéSimplex Method (Linear Programming Theory)
11.Rubioer Sradrecube)byLaplace.
12,Leplacee Malhod frODES
1,Non-Lunean one's Colver)
14,
15.
16.
1.
®
1
_.lina(CassinSSisldodséee
bos ‘ida a 4\
, FFL aye.
QD =GD=Ye Avidiecepom® ge SR=P= 30) _DBs GATS Giteet
; LEY-42Tay aesranance froienenn.
iaet a
if Porgy . -
7Sample > Provfata."
cRO Yom PloyA————_3“SN. aw yaa. 4
Derwab noe ati
=BGYl=Alapaha] A=Be
>§Q=Rey2+69
-Ma)ag*8H)ae
&Rewme az.
R= PO). BOD» _Roly) BOS)yLag" Laat amy” 20
GConoral Araubt:
Y=96=¥0
Qherawnmssarovke!(5),K2l5)----Xm(y)-Tron me
is
aadonFrarpled. Sagwse y=xband
~¥/(er . Boo=ge 04
ThPals)=[Palifq)+Px(-3)\=RS) ay23
.
=1.1ol) aellfareky Vary?
; =aSSham Ww(21-105), “
Frongt#3
a* 2«
R= er ew)
LES PD
bhont:(21-139) Lt=ac)’SC)v5(2)moe:IQ Ase?6.1.34
+ ntl a 4Spe WL=(ae*)(erya(p28? 4 rs)Stns{z65gketVLE9=(20°):nes)=2owa=note
ray
Qn! yLOG =(moSE(arol=MOD0
Amd =ot[m2ar
&
| - seekKalfy>alee de
©Rosheds) |
Ly=Saasicy=Varn2RG).
Japletfy dibsde
=[30295Rls)
=bide
Se}aa.
Ll)
=ab[wet-20° 2)
Vous oe .
___negAteePre
e caf=cummuletiia dikCdn @ é
Cano.50Lan) AR=prob.dausity Sohnemocass 9 28oiarrareorwanae:vans? LCVAPTER2PRORABILTTYANDsTOCHAS!
Thisconditional cdfsatisfiestheproperties previously established forthese hy r nw functions, suchas
iSntCRE Ce en wa one j Fact Resins ot)0 ; StatisticallyIndependent Random Variables, Wehavealready defined * * a . Statisticalindependence oftwoormoreeventsof«samplespaceS.The “ conceptofstatistical independence canbeextended torandom variables definedonasimple spacegenerated byacombined expcriment orbyrepented Wilofasingleexperiment. theexperiments resultinmutually excuse AE “outcomes, theprobabil ofanoutsome inoneexperiment iindependent of aManoutcome inanyotherexperiment. Thatis,tRejointprobability ofthe a nooutcomes factorsinto@productoftheprobabilities corresponding toeach 4 heeycome. Consequently. therandom variables corresponding totheoutcomes fe :intheseexperiments areindependent inthesensethattheltjointpllocone
ino product ofmarginal pdfs.Hence themultdimensionl random variables .
, arestatistically independent ifandonlyif by COFostka)=FlaPU)+Flea) easy BBE snotadovalXondanexampleofhesept MIGURE214Atinatfomatin ofad oralternatively,
ane POF)=pley)oCea)Pls.) 2138) : 21-2Functions ofRandom Variables
.
jferentiating (2-1-40) withrespect toy,weobtain therelationship Aroletateiseeninpracaspcatnsofprobabilityisthe Byieretnting 0)wihep following. Givenarandom variable X,which ischaracterized byitspdfp(x), q vedetermine thepdfoftherandomvariableY=g(X),whereg(X)issomegivenif dy)=4p1(=)v (24-41) functionofX.WhenthemappinggfromXto¥isoneto-ones the ; Poly)=PTsecs of70)eeiayfunptrar. Howerenthe thon(4-40)and(2-4)seytnerythrandvile¥ Deverertourfesvatonotpiyy namewienY=,west HS intemoaftheifanepaloftherandomvariablefortheTear” ie transformation in(2-1-39).Toillustratethismappingforaspecificpdf Example 24-1. ‘
x(x), consider theoneshown inFig.2-1-4(6). Thepdtpr(y) thatresults ‘Considertherandom variable ¥defined as ce fromthemapping in(2-1-39) isshown inFig.2-1-4(¢).
Yaox+d (24-39) a Whereaandbareconstants, Weassumethat@>0.Ifa<0,theapproach is Example 24-2 similar(seeProblem 23).Wenotethatthismapping, ifustated inFip . Consider therandomvariable¥definedas 2-1-4(a)islinear andmonotonic. LetFy(x) andFy(y) denote theedfsfor¥
: > a andY,respectively.t Thenv — Y=axX?+b, a>0 (2-1-42)
y - isone-to-one. Hence Fo)=Posy}=Pox+b<y)=A(xettY q ‘AsinExample2-1-1,themappingbetweenX~rcone.He rome -b By)=PUYsy)=Plax?+b<y) =Bac=A(2=2
. ot 7 JOpniBide=(2)Ae140)HRs oof2)"Jen(@Z)"] 4%een 1Toavoidcontusion inchanging variahtes, subscripts areusedintherespective palssnddl. - «
DorC.Proakin, DaLensBerdEk,1995),MeGrou-ttl
Ria Distribution --fromMathWorld file:///D:/Work/My%20Interests/Math/temp/Binomial%20Distribut...
WOLFRAMRESEARCH athworid.wolfram.com THERWON
ProbabilityandStatistics>StatisticalDistributions»DiscreteDistributions¥ eMMeteor» Trott -
MATHEMATICS
—"Binomial Distribution™
_
palatal rt,Dy FB]MattomotcoNetaboskithMathteader
EiconPes5
Romie lary |
pokingeee
FRirnienca pio
orto Sig]ThebinomialdseibutiongivesthedisreteprobabilitydistibutionFe(OI)of PAE Re: Pa Bn ei5a5YgeobtainingexactlymsuccessesoutofNBernoullitrials(wheretheresultofeach @i:erehigo") Bernoullitialitruewithprobability pandfalsewithprobability4=1~P).The Rie binomialdistributionisthereforegivenby
iancous: =fovea it Roly=(Nar @
[imesommeies® fal =alway?" pe), Q)
, where (%)isabinomial coefficient. Theabove plotshows thedistribution of1
successes out ofN=20trialswithP=@=1/2,
The probability ofobtaining more successes than thenobserved inabinomial
distribution is
x
P=(Dota-n¥-*=43,0—m), @) ey
where
B(e;a,0) a,b)= 4 t) 426)=Fay @)
lof7 1/21/2005 6:34 PM
Chapter 7
Probability
7.1. Experiments, Sample Spaces and Events
Startwithsomedefinitions wewillneedinourstudyofprobability.
AnEXPERIMENT isanactivitywithanobservable result.Tossingcoins,rollingdiceandchoosingcardsareallprobability experiments.
Theresult oftheexperiment iscalled theOUTCOME orSAMPLE POINT. Sothetwopossible outcomes from tossing acoin areH(heads)andT(tails).
r)‘ThesetofalloutcomesorsamplepointsiscalledtheSAMPLESPACEofthe experiment.
AnEVENT isasubset ofasamplespace.Thatis,aneventcancontainoneormoreoutcomesthatareinthesamplespace.
Consider tossing acoin. Thesample space isS={H,}. Theevents thatarepossible inthis experiment are@,{H}, {T"}, 8.So,while
there are2outcomes inthesamplespace,thereare4differentevents.
Ifa6-sided dieisrolled, thesample space isS={1,2,3,4,5, 6}.
Sometimes weuseatree diagram tofind allthepossible outcomes ofanexperiment. Consider tossing acoin 3times andnoting the
resultofeach toss.
fint second tind tome
HHHHre 7 HHT
H H HTHTKTHIT
H<CHTHH T T THT
rSsTIT [email protected]
S$=(HHH, HHT, HTH, HTT, THH,THT,TTH,TTT) Y
7Gaice Bpscin 1998, 1999, 2000. These notes maynotbedistributed forprofit
Teroa AEM
»LevieCivita symbol andcross product vector/tensor Page Iof5
Levi-Civita symbol and cross product
e vector/tensor
Patrick Guio
$Id: levi-civita.tex,v 1.9 2001/08/29 15:53:02 patricg Exp $
Definitions
TheLevi-Civita symbol¢,,,isatensorofrankthreeandisdefinedby
0, ifany twolabels arethesame
ijk=1,if,9,&isanevenpermutation of1,2,3 ()
1, ifi,j, bisanoddpermutation of1,2,3
TheLevi-Civita symbol ¢,,,isanti-symmetric oneachpairofindexes.
Thedeterminant ofamatrix 4withelements q,,canbewritten intermof¢,,,as
e i42a3 3.33det]a2i22ans|=>>>) eyaariaryacy =eynariarjase =<— (2)
431 32 G3 isi j=1 k=
Note thecompact notation where thesummation over thespatial directions isdropped. Itisthisone
that isinuse.
Note thattheLevi-Civita symbol cantherefore beexpressed asthedeterminant, ormixed tripleproduct, ofanyoftheunitvectors (6,é,,é,)ofanormalised anddirectorthogonal frameof
reference.
=det(é;,8,84)=8+(8)Xe, @) eajk=dot(&i, €;,2x)=B:-(8;xen)
Now wecandefine byanalogy tothedefinition ofthedeterminant anadditional type ofproduct, the
vector product orsimply cross product
a: @ ésaxb=det} ara2a3|=eyedsayy ®
by ba bs
or eachcoordinate
(aXb)i=eijnasbe (5)
http://folk.uio.no/patricg/teaching/al 12/levi-civita/ 2/11/03
.LevisCivita symbol andcross product vector/tensor Page 2of5
.
Properties
©.TheLevi-Civita tensorej,has3x3x3=27components.
©3x(641) =21Components areequal tog.
3components areequal to1.
3components areequal to1.
Identities
TheproductoftwoLevi-Civita symbols canbeexpressed asafunction oftheKronecker's symbol,,
€ijeEimn =t6djmbin +bimdjndit +Sindee
bindjtbun—6:18jndkm —Sindjmndet (6)
Setting ;=1gives
igh€imn=5jmdtn—5jn5km (1)
or
CijkCimn =S44(SjmOun —5jn5km) +dimdjndei+bindjidem—SimdjiSkn —SindjmSki
=3(8jm —Sjndim) +Stmdjn +5jndtm —5jmbtn —Stndj
=Sjmbin —5jn5km
Setting ;=;andj=mgives
ajkeijn =2kn @)
Setting ;=1,j=mandx=n gives
encys =6 ®
Therefore
ax(bxe) =b(a-¢) —e(a-b) (10)
proof
http://folk.uio.no/patricg/teaching/al 12/levi-civita/ Jrontiunsin, dasaf2/11/03
co Roark Liteyohoy UCB.
e . xPhysics 209 oavadsm Raaey.
Fall 2002
Notes 3
The Levi-Civita Symbol
‘The Levi-Civita symbol isuseful forconverting cross products and curls into thelan-
guage oftensor analysis, and formany other purposes. The following isasummary ofits
most useful properties inthree-dimensional Euclidean space.
‘The Levi-Civita symbol isdefined by
1,_if(ijk)isanevenpermutation of(123); cise=41,if(ik)isanoddpermutation of(123); (3a)0,|otherwise.
Tthas 27components, ofwhich only 6arenonzero. Itfollows directly from this definition
that e;js,changes sign ifanytwoofitsindices areexchanged,
ijk=jak=Chey=—Ejik =ekg =Ege (3.2)
e ‘TheLevi-Civita symbolisconvenient forexpressing crossproducts andcurlsintensornotation. For example, ifAand Baretwo vectors, then
(AxB)i =eyeAjBry (3.3)
and opNk
(xB). =canFE. (3.4)
‘Anycombination ofanevennumberofLevi-Civita symbols(oranevennumberofcross.
products andcurls) canbereduced todotproducts with thefollowing system ofidentities.
Similarly, any combination ofanodd number ofLevi-Civita symbols (oranodd number of
cross products andcurls) canbereduced toasingle Levi-Civita symbol (oracross product
oracurl) plus dotproducts. The first isthemost general:
Se Sim Sin
ijkCtmn=|55eSimbin|+ (3.5)Sie Sim dn
Notice that theindices (ijk) label therows, while (¢mn) label thecolumns. Ifthis is
contracted oniand J,weobtain
83min cansinn=|GS|=bmban~BnSi (6)
2
This identity istheoneused most often, forboiling down twocross products that have one
index incommon, such asVx(AxB). Bycontracting Eq.(3.6) injandmweobtain
ijk€ijn=en (3.7)
Finally, contracting onkand nweobtain
ijkijn=8. (3.8)
Itshould beclear how togeneralize these identities tohigher dimensions.
IfAy=—Ay isanantisymmetric, 3x3tensor, ithas3independent components that
wecan associate with a3-vector A,asfollows:
0 Ay Ap
Ag={-As 0Ar|seinAn. (3.9)
Ag -A, 0
‘The inverse ofthis is
1Ais=5eunAte (3.10)
‘Using thes identities, themultiplication ofanantisymmetric matrix times avector can be
reexpressed interms ofacross product. That is,if
rd Xi=Ay¥j (3.1)
then
X=YxA. (3.12)
Similarly, ifAand Baretwovectors, then
A;B; ~AjBi =jk(AXB)x, (3.18)
and OB,OB;FeBe=OH(TXBDe (3.14)
Finally, ifMi; isa3x3matrix (ortensor), then
1 detM=eijxMaiMajMax =GeijhetmnMieMjmMen- (3.15)
‘TheLevi-Civita symbol hasbeen defined here only onR°,butmost oftheproperties
above areeasily generalized toR"(including thecase n=2). Itonly transforms asa
tensor under proper orthogonal changes ofcoordinates, which iswhy weare calling ita
“symbol” instead ofa“tensor.” Itcan, however, beused tocreate so-called tensor densities
onarbitrary manifolds with ametric, and hasfascinating applications inHodge-de Rham
theory indifferential geometry.
7- Simon Malhams wwwma hwiac.uk/~ simon ™
| Wholesotdirwrtoodad \.
CHAPTER 5
Method ofstationary phase
‘This method was originally developed byStokes and Kelvin inthe 19th
century intheir study ofwater waves. Consider thegeneral Laplace integral
inwhich 4(¢) ispure imaginary, i.4(¢) =iv(t) sothat
5
I(2)=[F(t)=Oat,
where a,b,2,f(t) and Y(t) areallreal. Inthis case, I(2) iscalled the
generalized Fourier integral. Note thattheterm eV!) ispurely oscillatory
and sowecannot exploit theexponential decay oftheintegrand away from a
maximum aswas done inWatson’s lemma and Laplace’s method. However,
ifxislarge, theintegrand inI(2) oscillates rapidly and sowemight expect.
approximate cancellationofpositiveandnegativecontributions fromadjacent t) intervals, leadingtoasmallnetcontribution totheintegral. Infactwehavethefollowing result.
RIEMANN-LEBESGUE LEMMA. If|f(t)| isintegrable andy(t) iscontinu
ously differentiable over a<t<b, but(t) isnotconstant over any subin-
terval ofa<t<b, then igap
6/—~—~I(x)=[FeO dt0as2+00.
——- Toobtain anasymptotic expansion ofI(x) asz—+00, weintegrate by
parts asbefore. This isvalid provided theboundary terms arefinite(Snd\the
gsulting integral exists; forexample, provided that f(1)/(t) issmooth over
@<t<b and non-zero at:either boundary, thenao du=&Al)wen FO) 1 paso ae ie Ta)=|2O_.wo-ifALO) oveayYW TSGal ee (@)(oo bf$(SB)ee Sarsinv aiee diret-08%F ah ‘The2ndintegral iso(2)asz++00bytheRiemann-Lebesgue lemma and44%= ¥~ ct at 3wk_2Cal f(t) .1 ~ 0) ~er 1)~[gy OPO]a8e400
ysIntegration bypartsmayfailifUt)hasastationary pointintherangeofintegration, ic.W/(c)=0forsomea<¢<b.Supposethatindeedy'(c)=0 e@forsome a<c<band W(Q) £0 forallf¥cin[a,b]. Then proceed as
follows:
1
Step 1.Forasmall ¢>0wedecompose I(z) toI(x;€)justlikein(77) forLaplace’s method. The remainder terms weneglect, forexample inthe
casewhena<c<b,are
[p(y at+fFM at A ove
and these vanish like 1/z asz—++00, as(t) hasnostationary points in
either interval, and wecan integrate byparts and apply theRiemann-Lebesgue
Jemma.
Step 2.With ¢small enough, inorder toobtain theleading order be-
haviour, wereplace f(#) and(t) bytheapproximations
He FOXFOandy(e)rw(o)+O. @-ep
This assumes y"(c) #0,otherwise wemust. consider higher order terms.
Hence weget,
I(2)~fFoF(MOSES) aeas2400.
Step3.Wereplace¢byinfinity—this againintroduces termswhichvan- ishlike1/asx—++00andwhichwillbeasymptotically smallertermsthat t) canbeneglected. Thensetting(achangeofvariables duetoMorse)
a2PO 6sen(y"@)
yields
2 a m2 I(x)~f(oe¥..f [ersen(¥")? dgas2too.(5.1) (2)~flo) aot te 6.)
‘Toevaluate theintegral ontheright, usethatf°,e##ds=Ve#*/4 so
that eventually weget
Tax)~fle)=WO+ieenco"(Oe/4. |27 ng, 400,
aly"(c)|
Note. Ifc= aor c=b, thecontribution from theintegral, which isonly
overasemi-infinite interval,meprtsthattheasymptotic resultabovemust. bemultiplied byafactor of4.VIf p(t)hasmany stationary points in(a,6],
then wesplit uptheintegral into intervals containing only one stationary
pointandein eachoneindependently (thoughtheircontributions are additive). “Again, therelative size off(t) atthestationary points of(2)
willnow beimportant. Ifthestationary point issuch that ¥/(c) =W"(c) =
s+=W™1(c) =0andyc) #0then make theapproximation W(t) ~
¥(c)+2212.-(t—c)™ instead.InthiscaseI(z)behaveslike2~1/"as«++00. r) Note.Alternatively, after(5.1),wecouldhavemadethesubstitution5=vel") */4andusedthatf°,e-dv=VF.
Example. Tofindtheleading order asymptotic behaviour of
A
I(2)-[cosz(t—t) dtas2+00, 0
wwefirst write theintegral intheform
1I(2)=Ref[eX?)at}f
sothat wecanidentify f(t) =1andy(t) =#—¢. Hence w(t) =31?—
1and w"(é) =6tsothat yhastwostationary points, ofwhich only the
positive oneliesintherange ofintegration atto=1/V3. Since y(t) =
6t>0for¢>0,this isalocal and global minimum; and finally note that
+b(to) =—2/(39/*). Hence truncating ourinterval ofintegration toasmall
neighbourhood oftg(this only introduces asymptotically smaller terms), we
then make the approximation
(to HO=vtto)+O) igy?
and then extending theendpoints ofintegration offtoinfinity (again only
introduces asymptotically smaller terms), wefinally get
H(z)~eevee)fotI-10)? dt,as2+00,
@ Makingthesubstitution s?=2-fe)+(t—to)?,generates
2 ooig? Qn T(z)~o2¥(to). [eit?dg=elle¥(to)+a/4) — © aT) Ie a)
Now taking thereal part ofthis, weget
ee10)~[aqex(Z- 2%)eo4
Tttacos(t-B) © “om tiacos(¢-$"divesie=Jigos(oseteed)=TO
— Jedkag =9d.(8) D@=aL Tlel=o
SOs =ad(*) fun3D=e
a
Te(be)de =alto(ab) i
js”
Set sina
.a={ouedx=2°
7 SELECTED DEFINITE INTEGRALS
r v T Jsomedx=LoosGrn)dx=asS3
0
JSMx4,== J)sanedeaCe(4mreBy x Q .x “Utlamdo
OR Oomee ~—<K 1jedx=a >o)
J@
J5“ 1 \Se%2 aJeKXdn= Jeede=28
<
\ >oxat 2. Jéxdx=ye Pad==)!°
Co 2 so 2~oX ™ =XX, ave\z Jeo =& exdx =Qua
coy “eeeoSRSSE Ub§~ex"an 4gS xdy=(Qn-1)}! iE(Qa) cvs
oo Ssitean=EF 5teake2S@-2)
“e .
Sedk=UT _ Jore 3 Fesimgnae=caeOa . :fExXdx= 2 sq =
: ike ‘ Cs}See =7,So. ey0ok on! JeKan=+Veh)Dash)RE 3 JePane Te. 3
; 7
Wore,sieteinlegaly S: Be eeee
Bo\neret- od Fle SES ga
- =Seen) TAP eT
a SasSMb@eGos] =RO. aT
\ Gea Vb) - oe e 4aye .
@Sova(x= BCat-\, Ht)—Jpaerok . LC
ae WA) es ~ ~ °
RoR SOR. ™:- - ©Shen) =Vhe hal- a. IZ
e re
7a ‘
a
ed
a ET NE
oS
oo ee>re Skese, desizds. corm2$43
——-Sae x7+5eo
:CECatsolare ot o Se
a de ne 9ae — +Gb)©|ets2aeet]__ig).9 G@-ay@-8)___
ws Ae8-1
ES
ae gua!TkeS sexe
Gannon X=ngaSaye
—Wal thS22 es
ty AG)Zooe
ee RecutSonosfreen\,Muteaoct tea
_ 7 en
—_ B=eset Feel, seman
wan he BD BL (na VONRUCYCn
—Sayonammet =82OA Oe _
a _S<ttoe Sareea ee_ oek2.G-Ale&) .-4G2). @-8) BAN
: . ~ =\ See -
2see eta 43> et.WAGER Spi aeS A,lehoweSommeSuga_ on _ . Oe
Sou_— See WAS Se
: <>)oss7i ns
—Sag-\asoaud>, sweAaahippoe
_—WE —dimwldaddsodelithdoasieloo.
;
7 oo ee — _
p> oakoa
ae are2 ortosesx a
mbit BoasadalesaSWOT
Rikpewadsoo0+S-.Ys sek
Ss a a =
re
— a a ee, a
—. Soxlososx iaB-akwOOsK ea
eo [ netik Saa>Vel Oaanal —_
th Matecenfinrnns972,70, 02D
_-—_—_ >_ __
(
WOR
oe8A RR
do ee, ——vo aesfla|~~ ChanC8 re Coe . .
UO
— Me --— ——- ——-- -..-—
aS
Ayat8 —--a. || ee2aklasosK dee
_
moda: a>lbl>o- a_asall ||
(NT
_Nat vr ttt—CSSCOCSESS
- ox Sinx a, 3 i
oO Site TeaS =Bears_= =a = Se
a
ee en——— ee ee — Mpecern —Aa
oo ee oe aee gtd, a>\blyo; abval|
(
a ee re
oboe. dL alecosa. anben8% =
_ se 3.na ~~ !!lUen ere ab ade LL>\b\0.A oe ne
——\ 8s. = \+—t—\ (2 6—bhepse, 2 atbeosy axbeose |\**/ 3:
— OA cos) TT
a wR aie oA at
es (Sy=—oos() Hr OO
we oeje emacetNET Bran—nee 2GE
& = \_ -
.
orakesucy za bsmy anbsna| - °
eea a
ne
=x a>\bl20a Ss coos aa
a
~\ode a\gx \ens cs ar2 9)ofeodn__alat=ee
/:
a
-nn eSmT oe yPra Ska .jot fe
_ |. a an —
1.Ne =TL an i _J2 waBeosx aaa oe
|ammiadtky jaseo 6abek
eT Ss
(
——voitEstee. -- ——
——srlpakaa0)Qossancfdh:Dru 2-2sfRaber
a —Yaelasesite]=aIdeSlonse,subel_ aa
Clea, suc catloan) =side ghoe tC ers) ete
— a
en
| dae psene,sel=Jaet\swle,cave| .
a -
aBe
fo
—Gonsinre, Votamala..._____- a= —
WoCine spreaDekeSpnyhPABdepods
—@Meo. ee ee _
Tes NaotCo
TT SAT. bs)=26 ys)
TGs) ==Tecate x(ble)
@tan2+Tea}Toca,b,s)»} (20)+Cola)
_ 2-8-03 There>Fanweaedaanad fieFe,8),poetics¢
: wehawSarl§d)=o
Prt: San(s.8) =rahe eGR)
wub=AfrdG+oSy +Ae(s)
OHaggseGE)=(Se) =Oswe$=fucka
— @=Sho Ladube)
.
=Sol, =OSwe amodac
SOSA aae=)MV\a0+SV-(FM)aL _>oo
TrudefF=f, seTe=tpg. J
. \Sh-GyaL=\8VydL
aayorwre“chotngpacts?oleBu'V.
mi} /0-3|-08 Kaopth ~ nn «si. LS at yy peWd
| an
ry (vtTHEVALUATIONOYCERTAININTEGRALS :3 TnChapterweencounteredinegralsovertheintermediate satesofthe :aarenpytina oc saante hi {5thecompatatinn be a raieatty tatrHt, “eden ntofrinhanngaen1Pet(ASH)reytineoteflfr, : yPoonaTieatoll nicoRay 1 fae : |semenPacemrteerntate tn artietn[ts :Tiewiaipritamienteccmad gpctinegaiewicen ft i Slybedeattheslothteleptinretheeasy x 1 uss i"raewconshemaatdthatlcompton ‘TagowaFowl a)Fa i‘Tharaethessdraningmtohsprocedure,Oneeons ‘Theintegrationsoethenewvariablesy+taaeite SOad baitaptctytatopalsoraaeIGAsmthatthedeny(A5-2)aadtherfore(AG)teeforSpe | SrolSmeelsdadedpsnog fogssc.Thenwcnwatefarpaola‘Gp icp eioe ‘ ee iifarte [eet
wees NAwesteseamacntgnesitss. natn ifAeterna eetetrad =fSeborsbywetheeatin i FStepsbnacal oles iat! eae 1eetntatharyvbwhinedeeyen-~,YoOh —— wn SESaepoets By «x narymac.Wefdwh+=
1 fenf FBS ees(aes) Poreriad fe ,fe tftdoofgg i= : ae oof SRrere yneersrnee aoarbeae poo:‘EliasAfaSentepoety naomi FernT4RYbp,5HARBASDfrapieThyCkthySahywisthandriolommetion ewewheeGR k te i qo-oo cogs7feHiberrtenet an2inthatthe oe egoe oy«hsslipthenteeateeetesaaeame, TFRPream,Pi1780 we “aaeparnetydineuoed inthoflowingection.
hae ee
Croanbeckgerrdyah5 AolagePm4M)gi J aleaoe Yt. be».
Brag. —Pfn\POn) Vm) Dede dye 1
ee
NANet Mle: BEAK
e ma
See Oy
qn"..Qe Df)=.Pw)
x§dadededpe pe e
heat We Arte leek
dobh %whl
Deginneralf®
Taywik=2.
e
agp Mn). Pw)
Ah Ool,2> 7x§dxdaeAeeCriPa foal
Ghar We Ares og iegek
sdedh SGraeooty~2)du.
Jet4e=Y%
Asymptotic series: Amathematical aside http://farside.ph.utexas,edu/teaching/jk |/lectures/node76.html
[af [previc
@_Nev"TeWKB.solutionsasUp:Elestomagnetic wavepropagation inPrevious:Reytracingin the
Asymptotic series: Amathematical aside
Itisoften convenient toexpand afunction ofthecomplex variable /(#)ininverse powers ofz:
As,Ai 1)=$0)[tots Sa], (890)
where (2) isafunction whose behaviour forlarge values of#isknown. If/(2)/#(#) issingular as
|2|-+00thentheabove series diverges. Nevertheless, under certain circumstances, theseries may
Stillbeuseful,
Thecircumstance needed tomake thispossible isthatthedifference between /(#)/#(#) andthefirst
n+1 terms oftheseries beoforder 1/#"*? ,sothatforsufficiently large 2thisdifference becomes
tdvanishingly small’Moreprecisely,theseriesissaidtorepresentJ(#)/$(#) asymptotically, thatis
°
Heeey, (891)
pao
provided that
Hs)_ssAp Tim{29/272 _Sy“?1}40, 892)
Inotherwords,foragivenvalueofn,thefirst"+1termsofthe series may bemade asclose as
desired totheratio#(#)/6(#) bymaking #sufficiently large/For eachvalueof#andmthereisan
erroroforder1/#%**“Sincetheseriesactuallydiverges, thereisanoptimum numberoftermsinthe
series usedtorepresent J(2)/#(2) foragiven value of#.Associated withthisisanunavoidable
error,As2increases,theoptimalnumberoftermsincreasesandtheerrordecreases.[] eConsider asimple example. Theexponential integral isdefined
lofé 11/22/2004 10:09 AM
Asymptotic series:Amathematical aside http://farside.ph.utexas.edu/teaching/jk /lectures/node76.htm!
get Bi(s)=fSa (893) e‘
Theasymptotic seriesforthisfunction canbegenerated viaaseriesofpartial integrations. For
example,
ov Pet ale) = - [Fae ($94)
( xContinuingthisprocedureyields ZSalt) 46=BE,&)
* ot =1)Pnt Bs)=—[p-2+3-344.sagf Fa a —— ster Peetn gayefo 3 +(-ytingne[Sa\eo (895)
* Ss$6)-SaG) =xé2%.
‘Theinfinite series obtained bytaking thelimit n+00diverges, since theCauchy convergence test
yields
im[2]—tien[2 e ite|=fn,[Ela y (896)
Notethattwosuccessive terms intheseries become equalinmagnitude forn==,indicating thattheoptimumnumberoftermsforagiven#isroughlytheintegernearest=.Toprovethattheseriesis asymptotic,we need toshow that
cogot iyotet(—1)™4(n 41}!fazo. (897)
=~ we=RRO)~SJ] 2.LSS This immediately follows, since
0grt 1of? oF ffart<omfett=55.SedeeL(898)
owe
Aene£0)-5.l9<CTGon!ER” Thus,theerrorinvolved inusingthefirstmtermsislessthan(n+1)!e* /s"*? ,which isexactly
thenexttermintheseries, Wecanseethatasnincreases, thisestimate oftheerrorfirstdecreases
andthen increases without limit. Inorder tovisualize thisphenomenon more exactly, let
J(s)= soxp(s) 2{s) ,andlet
es(-1)Ppt ®Jafz)=>Ure (699)y=0
20f6 11/22/2004 10:09 AM
Asymptotic series:Amathematical aside hutp:/farside.ph.utexas.edu/teaching/jk /lectures/node76.htm)
@_theasympotc seriesrepresentation ofthisfunctionwhichcontains*-+1terms.Figure16shows
therelative error intheasymptotic series |/n(#) ~J()]//(=) plotted asafunction ofthe
approximate numberoftermsintheseriesnfor#=10.Itcanbeseenthatasnincreases theerror
initially falls, reaches aminimum value atabout n=10,andthen increases rapidly. Clearly, the
optimum number ofterms intheasymptotic series usedtorepresent /(10) isabout 10.
Figure
16: The
relative
error ina
typical
asymptotic -). seriesplottedas¥/ afunetion
ofthe
number of
terms in
the series
@ Asmpioric seriesarefundamentally differenttoconventional powerlawexpansions, suchas
et oat ings pe ye, (900) sases—ata at 0)
This series representation ofsine converges absolutely forallfinite values of=.Thus, atany#the
error associated with theseries canbemade assmall asisdesired byincluding asufficiently large
numberofterms. Inother words, unlike anasymptotic series, there isnointrinsic, orunavoidable,
error associated with aconvergent series, Itfollows thataconvergent power lawseries representation
ofafunctionisuniqueinsidethedomainofconvergence ofthe series. Ontheother hand, an
asymptotic series representation ofafunction isnotunique. Itisperfectly possible tohave twodifferent asymptotic seriesrepresentations ofthe same function, aslong asthedifference between the
two series isless than theintrinsic error associated with each series. Furthermore, itisoften thecase
that different asymptotic series areused torepresent thesame single-valued analytic function in
different regions ofthecomplex plane.
Forexample, consider theasymptotic expansion oftheconfluent hypergeometric function #(a,¢,2) .
Thisfunctionisthesolutionofthe differential equation
e aP"4(c—2)P’-aP =0 (901)
30f6 11/22/2004 10:09AM_
Asymptotic series: Amathematical aside http://farside.ph.utexas.edu/teaching/jk |/lectures/node76.html
which isanalytic atx=0[infact,¥(,¢0) =1).Here,‘ denotes ¢/42.Theasymptotic expansion
r)ofP(a,e,2)takestheform:
roem) Flojee) &Te—a)s*oF[1 +O(1/2)]
+0(a)z-*o™ [1+O(t/a)] (902)
for—™< arg(z) <0, and
Fee=2)aha,c2)~De~o)e**ef[1 +O(1f2)}
+0(a)a-*e'™ [1+O(1/2)] (903)
for0<arg(2)<m ,and
Horena) Payee)©Ele—a)atem)oF[14O(1/2)]
t) 40(a)e-*e!™ [1+0(1/2)} (904)
for*<arg(z)<2m,eic.Itcanbeseenthattheexpansion consists ofalinearcombination oftwo
asymptotic series (only thefirsttermincachseries isshown). For|#|>1,thefirstseries is
exponentially larger thanthesecond whenever Re{) >0.Wesaythatthefirstseries isdominant in
thisregion, whereas thesecond series issubdominant. Likewise, thefirstseries isexponentially
smaller thanthesecond whenever Re(z) <0,Wesaythatthefirstseries issubdominant andthe
second series isdominant inthisregion.
Consider aregioninwhichoneorotherofthe series isdominant. Strictly speaking, itisnot
mathematically consistent toinclude thesubdominant series intheasymptotic expansion because its
contribution isactually less than theintrinsic error associated with thedominant series [this error is
(1/2)timesthedominant series,sinceweareonlyincluding thefirstterminthisseries].Thus,ata
general point inthecomplex plane theasymptotic expansion simply consists ofthedominant series.
However, thisisnotthecaseintheimmediate vicinity ofthelinesRe{z)=0:thesearecalledthe
anti-Stokes lines.Whenananti-Stokes lineiscrossed,adominant seriesbecomessubdominant and @viceversa,Intheimmediate vicinityofananti-Stokes lineneitherseriesisdominant,soitis
mathematically consistent toincludebothseriesintheasymptotic expansion.
40f6 11/22/2004 10:09 AM
Asymptotic series: Amathematical aside bttp:/farside.ph.utexas.edu/teaching/jk/ectures/node76 html
‘Thehypergeometric function F(4,¢,) isaperfectly wellbehaved, single-valued, analytic function in
thecomplexplane.However, ourtwoasymptotic seriesare,ingeneral,multi-valued functionsinthe e complex plane [seeEq.(4.252a)]. Canasingle-valued function berepresented asymptotically bya
multi-valued function? Theshortanswerisno.Wehavetoemploydifferent combinations ofthe two
seriesindifferent regionsofthecomplex planeinordertoensurethatF(a,¢)2) remains
single-valued. Equations (4.252)showhowthisisachieved. Basically, thecoefficient infrontofthe
subdominant series changes discontinuously atcertain values ofarg{#) .Thisisperfectly consistent
with F(@,¢,2) being ananalytic function because thesubdominant series is“invisible”; i.c.,the
contribution ofthesubdominant seriestotheasymptotic solutionfallsbelowtheintrinsic errorassociated withthedominant series,soitdoesnotreallymatterifthecoefficient infrontoftheformerserieschangesdiscontinuously. Imaginetracingalarge circle, centred ontheorigin, inthecomplex
plane. Close toananti-Stokes line, neither series isdominant, sowemust include both series inthe
asymptotic expansion. Aswemove away from theanti-Stokes line, oneseries becomes dominant,
which means thattheother series becomes subdominant and, therefore, drops outofourasymptotic
expansion. Eventually, weapproach asecond anti-Stokes line, andthesubdominant series reappears.
inourasymptotic expansion. However, thecoefficient infront ofthesubdominant series when it
reappears isdifferent tothatwhich ithadwhen itdisappeared. This new coefficient iscarried across
thesecond anti-Stokes line into theregion where thesubdominant series becomes dominant. Inthis
new region, thedominant series becomes subdominant anddisappears from ourasymptotic expansion.
Eventually, athird anti-Stokes lineisapproached andtheseries reappears, but,again, with adifferent
coefficientinfront.Thejumpsinthecoefficientsofthesubdominant seriesarechoseninsucha e@ mannerthatifweperformacomplete circuitinthecomplex planethenthevalueofthe asymptotic
expansion isthesame atthebeginning andtheendpoints. Inother words, theasymptotic expansion is
single-valued, despite thefactthatitisbuilt upoutoftwoasymptotic series which arenot
single-valued. Thejumpsinthecoefficient ofthe subdominant series, which ateneeded tokeep the
asymptotic expansion single-valued, arecalled Stokes phenomena, after thecelebrated nineteenth
century British mathematician SirGeorge Gabriel Stokes, who first drew attention tothiseffect.
Whereexactlydoesthejumpinthecoefficient ofthesubdominant seriesoccur?Allwecanreallysay
is“somewhere intheregion between twoanti-Stokes lines where theseries inquestion is
subdominant." Theproblem isthatweonly retain thefirstterm ineach asymptotic series.
Consequently, theintrinsic errorinthedominant seriesisrelatively largeandwelosetrackofthe
subdominant series very quickly after moving away from ananti-Stokes line. However, wecould
include more terms ineach asymptotic series. This would enable ustoreduce theintrinsic error inthe
dominant seriesand,thereby, expandtheregionofthe complex plane inthevicinity oftheanti-Stokes
lineswherewecanseeboththedominant andsubdominant series.Ifweweretokeepaddingtermsto
ourasymptotic series, soastominimize theerror inthedominant solution, wewould eventually beforcedtoconclude thatajumpinthecoefficient ofthesubdominant seriescanonlytakeplaceon
those lines inthecomplex plane onwhich Im{s} =0;these arecalled Stokes lines. Thisresult was
firstprovedbyStokesin1857.150n aStokeslinethemagnitude ofthedominant seriesachieves its
‘maximum value with respect tothat ofthesubdominant series. Once weknow thatajump inthe
coefficientofthesubdominantseriescanonlytakeplaceataStokesline,wecanretainthe t subdominant seriesinourasymptotic expansion inallregionsofthecomplex plane.Whatweare
basically saying isthat, although, inpractice, wecannot actually seethesubdominant series very far
away from ananti-Stokes linebecause weareonly retaining thefirstterm ineach asymptotic series,
50f6 11/22/2004 10:09AM
Asymptotic series:Amathematical aside http://farside.ph.utexas.edu/teaching/jk I/lectures/node76.htm!
wecould, inprinciple, seethesubdominant series atallvalues ofarg(2)} provided thatweretained a
esufficientnumberoftermsinourasymptotic series.
anti-Stokes tine
nD SE
branch cut
Figure17:ThelocationoftheStokeslines(dashed),
theanti-Stokes lines (solid), andthebranch cut(wavy)
inthecomplex plane fortheasymptotic expansion of
thehypergeometric function
Figure17showsthelocationinthecomplexplaneoftheStokesandanti-Stokes linesforthe @_esymptotic expansion ofthehypergeometric function.Alsoshownisabranchcut,whichisneededto
make #single-valued. Thebranch cutischosen suchthatag(2}=0 onthepositive realaxis.Every
time wecross ananti-Stokes linethedominant series becomes subdominant andviceversa. EverytimewecrossaStokeslinethecoefficient infrontofthe dominant series stays thesame, butthat infrontofthesubdominant seriesjumpsdiscontinuously [seeEqs.(4.252)]. Finally,thejumpsinthe
coefficient ofthesubdominant series aresuch astoensure thattheasymptotic expansion is
single-valued.
all |previc
Next: TheW.K.B. solutions asUp: Electromagnetic wave propagation inPrevious: Raytracing in
the
Richard Fitzpatrick 2002-05-18
60f6 11/22/2004 10:09 AM.
WVAVG 28
Onedss+Aepait(-~05,Diyrora Socker| Gaussian Quadrature.
Theorem: suppose youhave apolynomial f(x) ofdegree 2n-1. Then theintegral
ofthis function over aninterval (a,b) against aweight w(x) isgiven exactly
bythisformular » ™
Jawa fe=SLAsm ¥= orl
Te, you get the integral exactly byadding upnnumbers. The function must
beevaluated atnmagic points (not2n-1points). Thex4arethezeros of
thepolynomial B(x) which isdetermined bytheweight function andinterval (a,b).
TheAj,called weights, aregiven bytheformula:
aASp783 Kiha(i)Bo. V(2-22) Kner SOD LyCHOY? > b.
This formula is discussed and derived below.
e ProofoftheTheorem: Trivial. Allyoudoiswritethepolynomial f(x)inLagrangian form andatonce yougetthat A;=INT( w(x)L,(x),x). Bychoosing
thexjinLy(x)tobethezerosofB(x), youmaketheevaluation ofA,very
easy, yielding the above simple formula.
This is, however, only aproof for f(x) being apolynomial ofdegree n.
Since theentire polynomial isspefified bynmumbers, itisnotverysurprising
that the integral can befound byevaluating the function atnplaces. Far
,
more interesting isthefactthat theformula isexact even iff(x) israised .
tobeapolynomial ofdegree 2n-1. What makes that true? Myway ofseeing this \
isnot the best but here itisanyway: Certainly everything isOKiff(x) is
ofdegree n.Imagine then that youhave found theweights A,andthezeros x;
using theabove derivation. Then ifyouexpand f(x) into itspowers, here
iswhat you have infact shown:
a , a y |
= "'yo= wR: Ke * MeBewyko> Spot AAYe
de,weknownowthat(*)isvalidforJ-0,1,2....n. Ifyoulike,thiscanbe @ taken asthe equation you solve for the Ajinamatrix sense. Ifwecan show
that (*)isinfactvalidforjintheextendedrafomthenwehave' ‘oven.what preatwewant BAzsw
decause then wejustmultiply both sides bybyanddotheextended sumto
conclude that theintegral formula isexact forapolynomial ofdegree 2n-1. ~‘Theproofthatformula (#)canbeextended inthiswayisgiven @
below. Itisbased onthe recursion relation for the orthogonal funetions.
Comments: thus wehave avery powerful result. Byknowing thevalue, sdy,
ofa7th degree polynomial atonly 4points, weknow the integral exactly.
There are ofcourse infinitely many 7th degree polynomials that run through
these four points, but they must all have the same integral. Notice that these
arenot4arbitrary points, butaréinfact 4very special points.
Accuracy: Suppose weworkwiththeneGause¥-Legendre“formila. Howdowe
estimate theaccuracy ofanintegral? Theaccuré¢y isperfect forpolynomial
ofdegree uptoand including 7. Where are the gaussian points?
| |L
' }
\ H nl ~~ |
5 '
Pye , \ '> i 1
- I ~
i
jv “i
R= (@) -2 44=381430190) $(s)=[NSxr0 fe+(8)(a):(6.6¥/0%)
This last shows an estimate ofthe remainder. You see that if the function
has no8th derivative formula isexact. BUt iffunction has deriviatives
that tend toincrease insize asyou gotohigher derivatives, then your
error may beimportant. The thing about apolynomial isthat its derivatives
keep getting smoother. Suppose you apply toan8th order polynomial. The
8ith derivative isperhaps oforder 1,more likely oforder 81!=40,000, so
error isatmost 2parts in 1000.
Arbbvious drawback ofthegoussien formulas isthetyoucannot
easily increase nasyoucaninSimpson's ruletoseeifresult issteble. @
( veuydoseuratactJennehuhhowe,ts?
———Swisrovkiwrs—____Dewdingy Ure.svnsateforenoon ste2mnh
@oS ak Rot De
eeZoom,BQ) oo
EE
NE mnheRyPomshsTBtyonehatSn=ZamAnls«Vowdo
nniia
eepA a ane i(wieGnee:) et
Qi. aa.Canes) 1ampCiotGwar), Te,Loebocoscksaleespidh
Ooo, nkbeeQU‘ XAEO1Cun (aes) =(mn) and (anr)mo” sme gm Ont) =o. _
YorQsVinWare).Gat2)=Cnet)arfete(me3~ 4 aun)Cmar so=1@(wert). Bukfaaie1@[lmtmtee)=269-004+16(9 A\csgorigDaearipelicnch Wenn. Gchmeeand1O(wei)Som,wintnmt £0sa ee
me) =VOQu) Cues)gummy: ruleLatoolFheCsi)seen)
2 Ces) +LOCme! KFdn(Qm~3). Fustedsanchs$3.0. Qs)42OCms) Naar Ascend ehrancher WONT 50
a Loe 2 OK,NON otetercomeneemailer EDont nVOns) gyreaedOF©astOY
Maa BetakQuelaseeeatDee
dm
=Ces)(amen)——iecamerADegaldinn. FA @ =2(Um~2)HO Pwr)|MO pewihelroane Arne
BOGm4OC NONevar iyghtenn
nome +eae) 2
Ve
m= 2eneosin see
a Oe ao 2bye QeOQ. Md Oe
08 ooCe0 ee
ig ee
-a&laesde st]=_¥da
_ - .-@\. wg a
—lseez+ier 2One, Za) AofoT
— a
poe *
--_Fonwule. fo.Nswisighle,inquvasalGaussian. inlayetsinn
1,You can get all these weights. byJust-inverting atertain matrixwhoseelements
;are various functions f, evaluated atthe zeros of one of the functions. It is
better andmoredirect though tousetheformula derived here.
_____2, Thenotation isacombination ofthatofScheidandAbram-Stegun. Iwilltryto
doeverything generally for allthe orthogonal polynomial systemscoveredinChapter 22oftheASbook, ____Im particular, herearesomesymbole Iwilluse: .
n= the order you are choosing. This isthe numberofserosxj.++++x, ,andthe
number ofweights Ay»The x;are zeros ofthe polynomial g(x). w(x)is
theweight function, andtheinterval is(a,b).
cy=defined onpage 773 - =defined onpage 778,given p-77
hy=defined onpage 77h _. =-coeff ofx”inB(n) ‘
Bpandgyrefer totable onpage 783which gives df,/dx. v
PI(x)means(x-x,)(x-x2)-+++++(x-%,) wherex,arethenzerosofA(x)_Yo. e1,(x)isdefined onpage53ofNumAnalSchwam.ThisisLagrangia® multiplier
function whichellowsyoutowriteapolynomial p,(x)ofdegreeninterms
ofthevalue ofthepolynomial atnarbitrary points p,(xj). Note that there
isnox,inourpresefn usage, butthereisonpage53.
_____(a) First,youhavetorealize thattheAjaregivenbytrivial integrals ofthe
______Legrangefunction, Thisiscompletely obviouse
——_____»—__ —____—_4 =»———-- ——___———— ---+--+ ---
cy cory ,
lm -
Bk $e)=2hmie) ess
-@— -->Ae Nano
SS
. =
__ biNext,“youobservethatthefunctions PLandPrt“whiehcanbeusedtogive
_____1y(x) exesimply related-to J,asfollows:6 {]
ob. =IK) oT
oe &@ =keOy= EWekwTaY
Bk oom9248/7" ALG=gee/g.00d}FG)Luca
_. TED =|.9.05)/08)] Sane 1RY ee
Tu TO bale yO
~___ (e)Weingtheformof1y(x),wethenwriteAyasintegral off.(x)/(G-x) Likesor
_. Leys gy Bato GS) oe
- a IO) OD KD
~~ |goSneak eeee HD KD a
(a) thenextproblemietofigureoutthisintegral. ‘hetrick1stotekethe—christoffel-Darbous formulasonpage785andepectalize toyex;.Tougets
_. ea(8redoC4))[in={-¥\md.(Ss}Yo
—- . we Kr Me wo a
_ WecansimplifytheHHSbyreplacing J...by.accordingto22Jh,since _____ dsaserooffj»Thus: ee --
oecaLn=2hBaal) aaesae _—FS AT Ne>nein —
oe a Gees
(.~
younowintegrate bothsidesofthissunruleagainst.the weightw(x),only Wore 3atornmurvtzenbecauseofrthogoneltty.’ Orthoggenerator tywhich_____-sancellle the_h,,ontheleftsoresultter
ee ee
ALDe OR HD
Nin
ButJ,isapolyofdegree sero,ie,aconstant, socallit$(2). Theseyoucan_
read off the table onpage 774, called stenderdization. Thus, when x,isone
ofthe zeros ofZyou may conclude thats a ———
$e —— —
ee K~Ki) Ki Kaa
oo
Vi PN OO) L x a
7 es erOenePe
NS beAR oo—_& @./g) 2
feaea
OO a mg
—}o)wd GS)kK ag Fk]bn
\
Ro Lew i:es et—Loe)-aGan
TO) AS Faw[a Pee ied|| 20
edeee eee _ —OL ood)oy|(VEN afeOO)ate _ a eee en ald eece —— -We Le css) | 2d gewea A _
0
yt
-@ eee
/ pakke Bok!
f
.
_____Hivst-Kind Gauss-Chubby Quadratame formlas;
eC
TES SE
Te WaneeRe the
e@[vite ten aeGetita |
oS
|
-—--_--Gauss-begendre-Quadazature-Formulast———— ~~~ ------_-___.
RY =Bed, BkMasaroseonsdkNaesaadforeTaLenng Tb19,OrnscsieenDarganasyyniarate
ee : _= - __© - » a
____ @Vrows_ 4|--—_. o5 ——__-—_-|
ani = ATO
ot
____Goments:_IthinkthisisthemostfamousGaussianintegration scheme.Aslight ‘oblemisthatyouhavetolookuporcompute theweights andzeros,sincethere donotexist closed formulas for'these things asoccurs intheChubby cases. But.
these arelisted andyouonlyhavetoenter themonceinaprogram todo-sueh
integration. ee
Acouracys see elsewhere. _ . ae
$$ eeSFeseeeeseee
( 4
pommel he2gftw
GUsaatbo. oassaaikfoalagaake,S\ayta\ Skbs Vlya
Dincak erent ee :
=2 Carb) = -a-b
ee =eyN yz §a= FCShkSVC]
ae
_-—whi =Gora)x+(otal oo :
i ee
— eeN
~-= fk aeeeFTQatse SLAs dAS|deere
—
TS eA Fond) +Boos e- = |
-—©+¥/_a ALCRnd aFex,4d) —.-..~Rsipn
bate ASAKa odBODoS (oma) 2
A= Noca)/2 ——$—
=co:A&A+xsx \ A~cx
_ ee a page 6ANS:
oecAltcen)+Ha-cxd] oo
_—A=.65214 SISSE 625% wy=BBANRIONS_RHEE
—__Ag= 287854895) BUSY =ROU GBS OSS
\3-
'.
. Puasa SO)watemsChae)Gurchion.wartleerdregs. tonaaonceoeoeeee eeQi).Ghen
i \ --Ah ~ -
-|SM@ax= ZuiSq)=Im i)|saTeDHSaeDeeomegamesehPC),anclolan
«ifwdoneTecemadewte whisksotue:Io. -MeLS - aa |e Sao=2BACT) m€(,™) <3)
© NeaTwbeautlan WinalesyosdeaddoLinkug. YnmsesCheened)Techedegoaance-codeudode TintCoypsumead20) andnumlasre aro),
‘nodeDra,wil Ad.ALsndreRoagen ArmAge mm€OmI},greainnagintSomeqinuniaghhe.+axteud!|Seo=z&:Ga) meG@,rm-1) WoGrce(mt,tur)
byeee onaeat.ag” tm “" powake 5CrN[Bbclay=fw)2roRcx]cawoptalely ask.
Swuamokiawel Srvieg(Mises) /TegatBdecunile 1g,
| Seegpmagreweekdetebeamtee.18S e weBe < aadofN)dewuato
m\edu deQrae,radd -_2“
masacid” =>n>ie®
A=24.
Raphore wily awdmu:
. ose"
A8stomCrn)
asain, UrtierDiemarr!SWEwdCOW)rel ; Masaural Rwayyweertyy(a).OK,wad
greey(tal),MansAxYAoenGnida =XG.) fousCarn)dg y-ie-e
Mort)waseecmtandqerenadvated:
AxJHCinsd)benho TH)den26Ref(rtsHQT
eats et Fryte e A®ayJS,eatass] seok(1)dw (weee° “20 : OndDassenogeedo18phenen&eeRN FA)ekdn. 4 ‘
L¥ 40s)anVva wens Chapter 1
a f£ b
Introduction
1.1 The mean value theorems
e First,weintroducethemeanvalueforintegrals.Assumethatfiscontinuous,then
= Ls(tdta=[sou=Parv
This 1iscalled thearithmetic average orthemean value offintheinterval
{a,2]. Westate themean value theorem forintegrals:
Theorem 1.1([1,p.258] Mean value theorem forintegrals).
Iffisacontinuous function on(a,2],then there exists anumber éin[a,z] such
that
ffHod=HeNa-a). a)
This isasimple butvery important mean value theorem ofintegral calculus.
|Itstatesthatthemeanvaluethoyger.ofacontinuous functioninaninterval‘a\belongstotherangeofthefunction, Anditassertsonlytheexistence ofatleast
1
one€,intheinterval forwhich f(€.) isequal totheaverage value offbutgives
nofurther information about thelocation .Inthisthesis, wecall&anintegral
mean point offon (a,x}.
Instead ofthesimple arithmetic average wecanform theweighted averages:
peLEf(tg(t)dtSeg(t)at
gistheweight function andg(t)>0.Wegivethegeneralized mean value theorem
forintegrals:
Theorem 1.2([1,p.257] Generalized mean value theorem forintegrals).
Iffis acontinuous function on(a,,gisintegrable on[a,2] and9>0,then
there exists anumber &.in(a,2]suchthat
[s@ateae= 106.)fFola. (12)
@ Obviously, Theorem 1.1isthespecialcasewheng(t)=1.
‘Theorem 1.3 ([1,p-197] Classical mean value theorem).
Suppose fiscontinuous ontheclosed interval [a,2]anddifferentiable on(a,x),
thenforsomeczbetween [a,2],wehave
1p.)
—£62)=f(a) iq) EX, (as)
Wecould estimate czas€inthesame wayasin(1.2). And wecallcea .
differential mean point offon(a,2]
‘Theorem1.4([1,p-198]Cauchy’smeanvaluetheorem).SeepropA
Suppose f,9arecontinuous on[a,2], differentiable on(a,2).Ifg(t) £0forany
t€(a,), then there exists cz€(a,x) such that
F(z)=f(a)_fC)= . 1.4) (2)—9(@)~ae) o#
2
e
| HerewecallczaCauchydifferential meanpointorsimplyCauchymeanpoint,
Recently, there areanumber ofstudies onthelocation oftheintegral mean
point £.,asz+ a.B.Zhang (7],improving B.Jacobson’s result [4],showed that,
iffisr(r€N)times differentiable ata,withf’(a) =f"(a) =... =fO-Y(a) =0
butf(a) #0,then
lim#—2-_1 |
eeG-a (+1)?
Schwind-Ji-Koditschek (5]went onfurther. They allow fandgtohave a'singu-
larity’ ata,Namely they showed that if
and
@ wherer£0,8>1,r-+3>—1,Ci,Cy£0,then
=a
Ontheother hand, ‘Tong andBraza {6}studied theconverse oftheclassical
mean value theorem. They showed that iff"(c) isnotalocal extremum, that ¢
isadifferential mean point.
Itseems tobewell-known that the four mean value theorems above are in-
terrelated. Infact, Theorem 1.3implies Theorem 1.1. Under some additional
assumptions, Theorems 1.1also implies Theorem 1.3. Similarly, Theorem 1.2
and Theorem 1.4areroughly equivalent. ‘Thus itisnatural tostudy theesti-
mates ofthe differential mean point and the converse ofthe mean value theorem
forintegrals.
3
e
Inthenext section, weshall discuss therelationships among themean value
theorems. InChapter 2,weshall firstdiscuss theworks ofB.Jacobson, B,Zhang
and Schwind-Ji-Koditschek onthelimiting position oftheintegral mean point
&.Then weshall prove corresponding theorems forthedifferential mean point
CzOftheclassical mean value theorem and Cauchy mean value theorem.
InChapter 3,weshall discuss theconverse oftheclassical mean value theorem
studied byTong andBraza. Then, weprove aparallel theorem forthemean value
theorem forintegrals.
1.2 Relationships among the mean value theo-
rems
@ ItisknownthatTheorem 1.3impliesTheorem 1.1.Thereisaproofinthe
Calculus book written byCampbell andDierker (3}.
Proof ofTheorem 1.1([3,p.209)).
Suppose f:{a,2] +Riscontinuous on[a,z]. Define F(t) =fff(s)ds. Then F
iscontinuous on(a,2]andF’=fon{a,x}. Hence byTheorem 1.3,there issome
cz€(a,2) such that
F(z) -F(a) =F(ce)(z- a).
That means,
[s@a=He\e-2). of(95U.)
Conversely, suppose FisC!and F’=f.So
F(e)—Pla)=f°float
4
ByTheorem 1.1and above formula, weconclude that
| F(e)~Flo)=[sat=1(6)(a-0)
Since Fisaprimitive off,wecould replace f(E2) byF"(E-) andobtain
mie) =Fla)=Fla)PQ)
Itisthesame form as(1.4). Thus ifFisC',then Theorem 1.1implies Theorem
1.3.
Yo(11.3)
Assume giscontinuous andg>0,then Theorem 1.4implies Theorem 1.2.
‘Theproofisasfollows: eDaf
FO=[fe)als)ds, Ge)=['o(s)ds.
FandGarecontinuous on(a,z]anddifferentiable on(a,z).Also
G(e)=[a(thdt>Gla)=0 gare
Hence weapply Theorem 1.4toobtain some c,€(a,z)such that
Fe)-Fle)=FIG) -(a)
ou | \
==HMeoles) ft froana=FESPoeae V
=He)food. y= (tay
5
of(4>2)
Conversely, under additional assumption onfandg,then Theorem 1.2implies
Theorem 1.4.IffandgarebothCl,let6=£continuous, @=g’>0for
simplicity, thenbyTheorem 1.2,thereexistsc,€(a,x)suchthat ®
[seateyat =oc.)[Poenar.
‘Therefore, L{{
[$0 FS[stow
So
Se)=F(a)_f'(ce)
(2)—9a)(Ce)* /
: of(esas)
6
PlanetMath: proofofextendedmean-value theorem hitp:/planetmath.org/?op=getobj&efrom=objectsid=3589
(moreinfo}Differential Equations Calculus SolverePlaneiMath O@rgaaS2-~- Sa
Mathforthepeople,bythepeople._Encilosedia|Requests|Forums|Docs|Random—E BuERG Login KorooPhf‘extendedmean-value theorem (Proof)
sreatenewuser |etf:[a,b]>Randg:[4,6]—Rbecontinuous on[4,8]and
name: [|==")itferentiable on(2;8),Definethefunction pass:v-beetvooworey|Pt)=£(2)(96)—9(@))—fz)(40)—£(@))—Fla)a®) +fOg(a)-
MainMenu Because fand9arecontinuous on[2,4]anddifferentiable on(2;8),sois
Wa Enoveloneodtah.Furthermore,h(a)=(6)=O80byRolle'stheoremthereexistsa Eapers€€(a,b) suchthat4'(€)=0.Thisimplies that
Expositions ©(9-9(@))-9GFO)—f(a)=0
meta
Requests 71) and,it9(b)#9(2),
Orphanage (10)Unclass'd FQ)_fO-f@
Unproven270) 6)—g(a)” e@Corrections(120) 7)a)a) vO
talkback
Polls
Forums “proofofextended mean-value theorem” isownedbypbruin.Feedback (viewpreamble)Bug Reports
View style: nmmagesBal somjewstyle:[HTCwismoosTlERI Snapshots.Snapshot SeeAlso:mean-value theorem
intormation othernames:proofofCauchy'smean-value theoremDocs ssobject’Classification Thisobject'sparent,News Cross-references: Rolle'stheorem,function,differentiable, continuous, Legalese
History Thisisversion3ofproofofextended mean-value theorem, bornon2002-11-12, modifiedChangeLog 2003-01-27.
TODO List Object idis3589, canonical name isProofOfExtendedMeanValueTheorem.
Accessed 1690 times total.
Classification:
“AMS MSC: 26A06 (Real functions ::Functions ofonevariable ::One-variable calculus)
e Pending ErrataandAddendaNone.
[View all4]
lof2 sad‘11:31AM.
PlanetMath: mean-value theorem http://planetmath.org/?0p=getobj &from=objects&name=MeanValu...
Dierentauations afrwater ree eran reeYueteeetawe ine5 Eto @ eastpeop,ytpele ‘ede|Rect|fone|05|aon[——— Losin nesnsabotecshatement oh — qgeatenewuserLetf:R—+Rbeafunctionwhichiscontinuous ontheinterval[2,4]anddifferentiable on(4,5).Then
ame:[J therensts@number©:2<¢<Bsuchthat pass:
aa s apfowvT ~10-4echoamiol fO-a (1.3) O) Main Menu
Encyclopaedia _Thegeometrical meaningofthistheoremisilustrated inthepicture:
PoserBooks 4
aoaRequests (71) oOSpt co 4inclass 4uneven ara y
Corrections (120) a
talkback “ Pats va Forums“
Feedback >
BugReports‘Thedashedlineconnectsthepoints(4;£(4))and(b,f(4)).Thereiscbetweenaandbatwhichthe r) downlosds tangenttohasthesameslopeasthedashedline. sreePMBook ‘Themean-value theoremisoftenusedintheintearalcontext:Thereisa©€(4,4]suchthat
ioraton
Docs
gas - e-a= [sede (ut) ®Lealese 4fe - History WThangstoa
fooous
“rneanvalutheoremisownedbymatuizard{iauthors(2)|nerbisory(1)
ew sea)
View tye: ia ER
‘See Also: Role's theorem, intermediate vale theorem, extended mean-vaive theorem, proof ofextended
tmean-vae theorem
‘Altachment:
proofofmeanvaluetheorem (Proof)bysaforrescomplex mean-value theorem (Theorem) bymatte.
Crosseferencs:nera tangent, heorm, dierenble ten contouous, fc
‘Thereare9references tothisobject.
‘Thisisversion6ofmean-value theorem, bornon2002-02-15, modified 2004-07-21.
Objectdis1890,canoricalnameisMeanValueThecrem. ryRoteasod8090tenestt
Classitcaton‘MSMSC"25406(eltmconsFincafnvalOnects)
1of2 10/14/2004 11:36 AM.
PlanetMath: proofofmeanvaluetheorem http://planetmath.org/?op=getobjéefrom=objects&id=2960
2)prtauton atausae2422 PlanetMath:@rgese r Be mae
e‘Mathforthepeople,bythepeople. Encylopedia|Requests|Forums|ace|aandom[jie
Login Aproofofmeanvaluetheorem (Prot)
sraatenewsser pene A() on[68]by
gg
SE| poss:———} - $0)=Ha) = AG)=s(0)~re)-(AIL)(oy
Peeters
7 Clearly, Aiscontinuous on[4,5], differentiable on(4,6), and
‘Main Menu
ssoctions h(a)=f(a)—f(a)=0Fistopeeda AO)=0)~$(a)—(AE)a)=0 Bases
Expositions NoticethatAsatisfies theconditions ofRolle'sTheorem. Therefore, byRolle’sTheorem thereexistscee, 06(ent)sucnat(6)=O
Regus
Orphanage ¢10) However, fromthedefinition ofAweobtainbydifferentiation thatere
‘Unproven e270) ‘ £8)=f(a) Canes 0 Ha)=se)-=L9.
takoackPolls since''(c)=0,wethereforehaveFons :Hat po=L0=8 (3)Aaoarert
‘BugReports b-a ecombats asronuited. .‘Snapshots Rolle=>CassienlPMBook Bibliography
ifomaton
Docs 1Classification MichaelSpivak,Calculus,3rded.,PublishorPerishInc.1994.News
aaese
Giaratog “protofeanvatharoswobyates TODOList (Viewpreamble)
Viewstyle:[HicwaninagesalSSIS
This object's parent.
Croneferocas: lusen,ats,ferentconus
This isversion2ofproofofmeanvaluetheorem,bornon2002-05-28, modified2002-05-29. Objectidis2960,canonical nameisProofOfMeanValue Theorem.sees antes ot
Classification:
AMSMSC:26A08(Realfunctions::Functions ofonevariable=;One-variable calculus)
Pending Errata and Addenda
Discussion
t) Style:[ThreadedBijExpand:[7ffOrder:[NewestetiMa
lof2 10/14/2004 11:37 AM.
PlanetMath: proofofRolle'stheorem http://planetmath.org/?op=getobj &from=objects&id=2947
or)DitterentialEquations GalculusSolver24/7 PlanetMath. @rg=a222~--Bae--~ @searsnepeo,pont othe|ResaEous|Osegann[a tanmo
sfeateneuuset’” Because fiscontinuousonacompact(closedandbounded)interval/=[2,8],itattainsitsmaximum pass— ‘andminimumvalues.incase£(2)=f(b)isboththemaximumandtheminimum,thenthereIsnothing
WEREmoreto-say,forthenJisaconstantfunctionandJ”=onthewholeintervalI.Sosupposeotherwise, srtyouss“and£attainsanextremumintheopeninterval(4;),andwithoutlossofgenerality,ltthisextremumbe Main Menuveiemaximum,considering~FinoutJasnecesary.WecantatthieentrerumF(6)wehave
peoede f= Own a<e<d,
Books
Expositions Toshowthis,notethat/(=)—f(¢)$0forau+€J,because£(c)isthemaximum. Bydefinitionof
mote thederivative, wehavethatResuaee79)phanage(0 2)-#00Unclass He)=tinLE-SO). ‘Unproven(270 =e ~Corrections(72)|ookingattheone-sidedlimits,wenotethat takback=tim{2-10 Polls Redae 8? ForumsFeedback ; ‘nthe z-e>0, ‘BugReports because thenumerator inthelimitisnonpositive intheinterval J,yet |,88xapproaches c
eSeana romtheright.Similar, ; domnioadsa,f2)-#0 ‘Snapshots L=limAII)59 anan yoe
Information SinceFisdifferentiable atc,theleftandrightlimitsmustcoincide,so9SL=RS0,thatistosay,Doos ¥Gassifcatin —F()=0.News
Legalese
HistoryShapaetoa “prottRoteesteomedbyenon[aur|unesey1)FOROst (viewpreambi
View style: [ivwininooosaBENRAE
‘This objects parent
Cross-references: differentiable, limit,numerator, one-sided mits,derivative, opehinterval, extremum, constant function,interval bounded, dosed. compact tantinoussetae
‘This version2ofpooofResthaoem,bornon2002-06-27,modified2004-0226. Onjectid's2047,cnonialnamesProofSRotes haorem. Releoved 1310 tines tl
Classification:AMSMSC:25408(Rete: Functofneva:Oarcai)
Pending Errata andAddenda
None. e@ [Viewall2]
lof2 10/14/2004 11:44AM.