设f(x)=(x-1)(x-2)……(x-n)/(x+1)(x+2)……(x+n),求导f'(1)

问题描述:

设f(x)=(x-1)(x-2)……(x-n)/(x+1)(x+2)……(x+n),求导f'(1)
我算的结果是(-1)^n/(n+1),

(-1)^(n-1)/(n(n+1)),