Найдите значение производной функции f(x)=4cos(2x+п/3) при х=п/3

Question

Найдите значение производной функции f(x)=4cos(2x+п/3) при х=п/3

Answer 1

!!!!!!!!!!!!!!!!!!!!!

---

Answer 2

F'(x)=(4cos(2x+π/3))'=
4•(-sin(2x+π/3))•(2x+π/3)'=
-8•sin(2x+π/3)
f'(π/3)=-8sin(2π/3+π/3)=-8sinπ=0