Gamma function limt to integral question











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I am reading up on the gamma function and have seen a formula that I can't connect to the usual integral definition. Namely,



$$
Gamma(x) = lim_{nrightarrow infty}frac{n!n^{x-1}}{x(x+1)cdots(x+n-1)}, qquad xneq 0,-1,-2,dots
$$



How can I connect this formula with the standard definition:



$$
Gamma(x) = int^infty_0 t^{x-1}e^{-t}dt
$$










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  • This is standard text book material. Any book that deals with Gamma function in detail has a proof.
    – Kavi Rama Murthy
    4 hours ago










  • This can be shown using the factorization of $frac 1{Gamma(z)}$, which can be derived from the functional equation $Gamma(z)Gamma(1-z)=frac{pi}{sin(pi z)}$.
    – lEm
    4 hours ago















up vote
0
down vote

favorite
1












I am reading up on the gamma function and have seen a formula that I can't connect to the usual integral definition. Namely,



$$
Gamma(x) = lim_{nrightarrow infty}frac{n!n^{x-1}}{x(x+1)cdots(x+n-1)}, qquad xneq 0,-1,-2,dots
$$



How can I connect this formula with the standard definition:



$$
Gamma(x) = int^infty_0 t^{x-1}e^{-t}dt
$$










share|cite|improve this question






















  • This is standard text book material. Any book that deals with Gamma function in detail has a proof.
    – Kavi Rama Murthy
    4 hours ago










  • This can be shown using the factorization of $frac 1{Gamma(z)}$, which can be derived from the functional equation $Gamma(z)Gamma(1-z)=frac{pi}{sin(pi z)}$.
    – lEm
    4 hours ago













up vote
0
down vote

favorite
1









up vote
0
down vote

favorite
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I am reading up on the gamma function and have seen a formula that I can't connect to the usual integral definition. Namely,



$$
Gamma(x) = lim_{nrightarrow infty}frac{n!n^{x-1}}{x(x+1)cdots(x+n-1)}, qquad xneq 0,-1,-2,dots
$$



How can I connect this formula with the standard definition:



$$
Gamma(x) = int^infty_0 t^{x-1}e^{-t}dt
$$










share|cite|improve this question













I am reading up on the gamma function and have seen a formula that I can't connect to the usual integral definition. Namely,



$$
Gamma(x) = lim_{nrightarrow infty}frac{n!n^{x-1}}{x(x+1)cdots(x+n-1)}, qquad xneq 0,-1,-2,dots
$$



How can I connect this formula with the standard definition:



$$
Gamma(x) = int^infty_0 t^{x-1}e^{-t}dt
$$







gamma-function






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share|cite|improve this question











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asked 4 hours ago









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  • This is standard text book material. Any book that deals with Gamma function in detail has a proof.
    – Kavi Rama Murthy
    4 hours ago










  • This can be shown using the factorization of $frac 1{Gamma(z)}$, which can be derived from the functional equation $Gamma(z)Gamma(1-z)=frac{pi}{sin(pi z)}$.
    – lEm
    4 hours ago


















  • This is standard text book material. Any book that deals with Gamma function in detail has a proof.
    – Kavi Rama Murthy
    4 hours ago










  • This can be shown using the factorization of $frac 1{Gamma(z)}$, which can be derived from the functional equation $Gamma(z)Gamma(1-z)=frac{pi}{sin(pi z)}$.
    – lEm
    4 hours ago
















This is standard text book material. Any book that deals with Gamma function in detail has a proof.
– Kavi Rama Murthy
4 hours ago




This is standard text book material. Any book that deals with Gamma function in detail has a proof.
– Kavi Rama Murthy
4 hours ago












This can be shown using the factorization of $frac 1{Gamma(z)}$, which can be derived from the functional equation $Gamma(z)Gamma(1-z)=frac{pi}{sin(pi z)}$.
– lEm
4 hours ago




This can be shown using the factorization of $frac 1{Gamma(z)}$, which can be derived from the functional equation $Gamma(z)Gamma(1-z)=frac{pi}{sin(pi z)}$.
– lEm
4 hours ago















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