how can you find the integral and the derevative of a simple factorial f(x)=x! (to find what f'(x) equals and what Sf(x)dx equals)? as i see it you have progressive multiplications, f(x)=x(x-1)(x-2)...*(x-k), which is the product of x-k where k=0 till infinity, should i take logarithms on both sides? if i have asked this before link me to the thread.(adsbygoogle = window.adsbygoogle || []).push({});

thanks in advance.

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# An integral and a deravative of a simple factorial

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