Question

Найдите экстремумы функций:
f(x) =sinx+cosx​

Answer 1

$f\left ( x \right )=sinx+cosx\\f'\left ( x \right )=cosx-sinx\\f'\left ( x \right )=0\Rightarrow sin\left ( \frac{\pi}{4}-x \right )=0\Rightarrow x=\frac{\pi}{4}+\pi k,k\in \mathbb{Z}$