设f(x)为二阶可导函数,且f(tanx)=1+sin^2x\cos^2x,求f''(x)是（1+sin^2 x）\cos^2 x

设f(x)为二阶可导函数,且f(tanx)=1+sin^2x\cos^2x,求f''(x)是（1+sin^2 x）\cos^2 x
设f(x)为二阶可导函数,且f(tanx)=1+sin^2x\cos^2x,求f''(x)
是（1+sin^2 x）\cos^2 x

设f(x)为二阶可导函数,且f(tanx)=1+sin^2x\cos^2x,求f''(x)是（1+sin^2 x）\cos^2 x
f(tanx)=1+tan^2x
所以f(x)=1+x^2
f'(x)=2x
f''(x)=2