单选题 设f(x)可导,函数y=f(sin 2 x),则微分dy=
【正确答案】 C
【答案解析】解析:dy=df(sin 2 x)=f'(sin 2 x)d(sin 2 x) =f'(sin 2 x)[-2sin xd(sin x)]=2sin xf'(sin 2 x)(cos xdx) =sin 2xf'(sin 2 x)dx. 选C.