Đáp án:
Giải thích các bước giải:
\(\begin{array}{l}
64)\\
\quad y = \tan2x + \cot2x\\
\to y' = \dfrac{(2x)'}{\cos^22x} - \dfrac{(2x)'}{\sin^22x}\\
\to y' = \dfrac{2}{\cos^22x} - \dfrac{2}{\sin^22x}\\
\to y' = 2(\tan^22x + 1) - 2(\cot^22x + 1)\\
\to y' = 2\tan^22x - 2\cot^22x\\
65)\\
\quad y = \cot(\sin5x)\\
\to y' = -\dfrac{(\sin5x)'}{\sin^2(\sin5x)}\\
\to y' = -\dfrac{(5x)'\cos5x}{\sin^2(\sin5x)}\\
\to y' = -\dfrac{5\cos5x}{\sin^2(\sin5x)}\\
\end{array}\)
