Question

设函数f (x) 可导,且y=f(tan^2x)则 dy/dx=

Answer 1

dy/dx = df{[tan(x)]^2}/d{[tan(x)]^2} * d{[tan(x)]^2}/dx = f'{[tan(x)]^2}*2tan(x)[sec(x)]^2

= 2tan(x)[sec(x)]^2f'{[tan(x)]^2}