오일러-가우스 초기하함수2F1
http://bomber0.myid.net/ (토론)님의 2009년 12월 7일 (월) 07:49 판
이 항목의 스프링노트 원문주소
개요
- 초기하급수로서의 정의
\(\,_2F_1(a,b;c;z)=\sum_{n=0}^{\infty} \frac{(a)_n(b)_n}{(c)_nn!}z^n, |z|<1\)
- 적분표현
\(\,_2F_1(a,b;c;z)=\frac{\Gamma(c)}{\Gamma(c-a)\Gamma(a)}\int_0^1t^{a-1}(1-t)^{c-a-1}(1-zt)^{-b}\,dt\) - 초기하급수를 해석적확
초기하급수로 표현되는 함수의 예
- 타원적분[[타원적분|]]\(K(k) =\frac{\pi}{2}\,_2F_1(\frac{1}{2},\frac{1}{2};1;k^2)\)
\(E(k) =\frac{\pi}{2}\,_2F_1(\frac{1}{2},-\frac{1}{2};1;k^2)\)
피카드-Fuchs 미분방정식
- \(\,_2F_1(a,b;c;z)\) 는 다음 미분방정식의 해가 된다
\(z(1-z)\frac{d^2w}{dz^2}+(c-(a+b+1)z)\frac{dw}{dz}-abw = 0\) - 초기하 미분방정식(Hypergeometric differential equations) 참조
타원적분과 초기하급수
-
제1종타원적분 K (complete elliptic integral of the first kind)
[[제1종타원적분 K (complete elliptic integral of the first kind)|]]\(K(k) = \int_0^{\frac{\pi}{2}} \frac{d\theta}{\sqrt{1-k^2 \sin^2\theta}} = \int_0^{\frac{\pi}{2}}\sum_{n=0}^{\infty}\frac{(\frac{1}{2})_n}{n!} k^{2n}\sin^{2n}\theta{d\theta} \)
(증명)
\(\int_0^{\frac{\pi}{2}}\sin^{2n}\theta{d\theta}=\frac{\pi}{2}\frac{(\frac{1}{2})_n}{(1)_n}\) (감마함수) 이므로
\(K(k) = \frac{\pi}{2}\sum_{n=0}^{\infty}\frac{(\frac{1}{2})_n(\frac{1}{2})_n}{n!(1)_n}k^{2n} = \frac{\pi}{2}\,_2F_1(\frac{1}{2},\frac{1}{2};1;k^2)\)
special values
\(\,_2F_1(a,b;c;1)=\dfrac{\Gamma(c)\,\Gamma(c-a-b)}{\Gamma(c-a)\Gamma(c-b)}\)
\(\frac{\pi}{2}\,_2F_1(\frac{1}{2},\frac{1}{2};1;\frac{1}{2})=K(\frac{1}{\sqrt{2}})=\frac{1}{4}B(1/4,1/4)=\frac{\Gamma(\frac{1}{4})^2}{4\sqrt{\pi}}=1.8540746773\cdots\)
재미있는 사실
역사
메모
관련된 항목들
수학용어번역
사전 형태의 자료
- http://ko.wikipedia.org/wiki/
- http://en.wikipedia.org/wiki/
- http://www.wolframalpha.com/input/?i=
- NIST Digital Library of Mathematical Functions
- The On-Line Encyclopedia of Integer Sequences
expository articles
- On the Kummer Solutions of the Hypergeometric Equation
- Reese T. Prosser, The American Mathematical Monthly, Vol. 101, No. 6 (Jun. - Jul., 1994), pp. 535-543
- Ramanujan and hypergeometric and basic hypergeometric series
- R Askey 1990 Russ. Math. Surv. 45 37-86
관련논문
- Transcendence of periods: the state of the art.
- M. Waldschmidt., Pure Appl. Math. Q. 2 (2006), 435-463.
- M. Waldschmidt., Pure Appl. Math. Q. 2 (2006), 435-463.
-
Exceptional sets of hypergeometric series
- Natália Archinard, Journal of Number Theory Volume 101, Issue 2, August 2003, Pages 244-269
- Natália Archinard, Journal of Number Theory Volume 101, Issue 2, August 2003, Pages 244-269
- Special values of the hypergeometric series III
- Joyce, G. S.; Zucker, I. J., Mathematical Proceedings of the Cambridge Philosophical Society (2002), 133 : 213-222
- Special values of the hypergeometric series II
- Joyce, G. S.; Zucker, I. J., Mathematical Proceedings of the Cambridge Philosophical Society (2001), 131 : 309-319
- Special values of the hypergeometric series
- Joyce, G. S.; Zucker, I. J., Mathematical Proceedings of the Cambridge Philosophical Society (1991) volume: 109 issue: 2 page: 257
- Werte hypergeometrischer funktionen
- Jürgen Wolfart, Inventiones Mathematicae Volume 92, Number 1 / 1988년 2월
관련도서 및 추천도서
- 도서내검색
- 도서검색
관련기사
- 네이버 뉴스 검색 (키워드 수정)