Bài tập 5.67 trang 209 SBT Toán 11

\(\begin{array}{l}
y\prime  = ({\cos ^2}x)\prime \cos ({\cos ^2}x).\cos ({\sin ^2}x) + \sin ({\cos ^2}x).[ - ({\sin ^2}x)\prime \sin ({\sin ^2}x)]\\
 =  - 2\sin x\cos x.\cos ({\cos ^2}x)\cos ({\sin ^2}x) + \sin ({\cos ^2}x).( - 2\sin x\cos x)\sin ({\sin ^2}x)\\
 =  - \sin 2x[\cos ({\cos ^2}x)\cos ({\sin ^2}x) + \sin ({\cos ^2}x)\sin ({\sin ^2}x)]\\
 =  - \sin 2x\cos ({\cos ^2}x - {\sin ^2}x) =  - \sin 2x\cos (\cos 2x)
\end{array}\)

-- Mod Toán 11 HỌC247