F'(x) если f(x)=lncosx^2

Question

F'(x) если f(x)=lncosx^2

Answer 1

F`(x)=(ln(cos(x²))=(1/cos(x²))*(cos(x²))`=(1/cos(x²))*(-sin(x²))*(x²)`=
=-(sin(x²)/cos(x²))*2x=-2x*tg(x²).