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tgamma

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tgamma, tgammaf, tgammal - ËÜÅö¤Î¥¬¥ó¥Þ´Ø¿ô

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#include <math.h>

double tgamma(double x);
float tgammaf(float x);
long double tgammal(long double x);

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 Gamma(x) = t^(x-1) e^-t dt ¤Î 0 ¤«¤é̵¸ÂÂç¤Þ¤Ç¤ÎÀÑʬ

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 Gamma(m+1) = m!

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 Gamma(x+1) = x * Gamma(x)

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 Gamma(x) * Gamma(1 - x) = PI / sin(PI * x)

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C99.

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gamma(3), lgamma(3)