Question

Derivative of sin11xcos11x

Answer 1

Hello here is a solution :
f'(x) =( sin11x)'cos11x +sin11x(cos11x)'
(sin(ax+b))'=a cos(ax+b)
(cos(ax+b))'=-a sin(ax+b)
f'(x) = 11 cos11xcos11x-11sin11xsin11x
f'(x) = 11(cos11x)²-11(sin11x)²