F (x) = cos^23x-sin^23x

Решить функцию

Ecli zadanie F (x) = cos²3x-sin²3x=cos (2.3x) = cos6x, to

F' (x) = - 6sinx

(cos 2α=cos²α-sin²α)

Ecli F (x) = cosˇ (23) x - sinˇ (23) x, to

F' (x) = (23cosˇ22x) (-sinx) - (23sinˇ22 x) (cosx) = - 23 (cosˇ22x. sinx+sinˇ22x. cosx)

Ecli F (x) = cos (23x) - sin (23x), to

F' (x) = - 23sin (23x) - 23cos (23x) = - 23 (sin (23x) + cos (23x))

Zadanie net točnoe ...