f'(x)=1/(1-x)²f''(x)=2(1-x)/(1-x)⁴=(1×2)/(1-x)³假设f(k)(x)=k!/(1-x)^(k+1)则当n=k+1时,f(k+1)(x)=k!·(k+1)·(1-x)^k/(1-x)^(2k+2)=(k+1)!/(1-x)^[(k+1)+1]k为任意正整数,因此对于任意正整数nf(n)(x)=n!/(1-x)ⁿ⁺¹令x=0,得f(n)(0)=n!/(1-0)ⁿ⁺¹=n!选A
CCCCCCCCCCCC