Question

y=sin^2(x)/(sinx)^2的导数

Answer 1

y=sin(x^2)/(sinx)^2用对数求导简单：

lny=lnsin(x^2)-ln(sinx)^2

y'/y=2xcos(x^2)/sin(x^2)-2sinxcosx/(sinx)^2

=2xcot(x^2)-2cotx

所以：y'=y[2xcot(x^2)-2cotx]