f(x)=(x^2-1)^1/2

问题描述:

f(x)=(x^2-1)^1/2

f'(x)=1/2(x^2-1)^(1/2-1)*(x^2-1)'=1/2(x^2-1)^(-1/2)*2x=x(x^2-1)^(-1/2)