[tex]\bf sin^2(x)+cos(x)\iff [sin(x)]^2+cos(x)\\\\
-----------------------------\\\\
\cfrac{dy}{dx}=2sin(x)cos(x)-sin(x)\implies 0=2sin(x)cos(x)-sin(x)
\\\\\\
0=sin(x)[2cos(x)-1]\implies
\begin{cases}
0=sin(x)\\
sin^{-1}(0)=\measuredangle x\\
\pi \\
----------\\
0=2cos(x)-1\\\\ \frac{1}{2}=cos(x)\\\\ cos^{-1}\left( \frac{1}{2} \right)=\measuredangle x\\\\ \frac{\pi }{3},\frac{5\pi }{3}
\end{cases}[/tex]
