Verified answer

Ответ:

f'(0) = 0

Объяснение:

[tex]\displaystyle f'(x) = \bigg(\sqrt{cos(x)} \bigg )' = -\frac{1}{2\sqrt{cos(x)} } *sin(x)[/tex]

[tex]\displaystyle f'(0) = -\frac{1}{2\sqrt{1} } *0 = 0[/tex]