Question

найдите производную функции

Answer 1

Ответ:   C .

$f(x)=cos^3(2x-1)\ \ \ ,\ \ \ \ \ (u^3)'=3u^2\cdot u'\ .\ \ u=cos(2x-1)\\\\\\f'(x)=3cos^2(2x-1)\cdot (-sin(2x-1))\cdot 2=-3\, cos(2x-1)\cdot \underbrace{2sin(2x-1)\cdot cos(2x-1))}_{sin(2\cdot (2x-1))}=\\\\=-3cos(2x-1)\cdot sin(4x-2)$