Cho

Câu hỏi: Cho $f\left(x\right)={\sin }^{5}ax,a>0$. Tính $f\text{'}\left(\mathrm{\pi }\right)$

A. $f\text{'}\left(\mathrm{\pi }\right)=5{\sin }^4\left(a\mathrm{\pi }\right).\cos \left(a\mathrm{\pi }\right)$

B. $f\text{'}\left(\mathrm{\pi }\right)=0$

C. $f\text{'}\left(\mathrm{\pi }\right)=5a.{\sin }^4\left(a\mathrm{\pi }\right).\cos \left(a\mathrm{\pi }\right)$

D. $f\text{'}\left(\mathrm{\pi }\right)=5a{\sin }^4\left(a\mathrm{\pi }\right)$