\(y=1-sin^2x+sinx+1=-sin^2x+sinx+2\)
\(\Rightarrow y=-\left(sinx-\frac{1}{2}\right)^2+\frac{9}{4}\le\frac{9}{4}\)
\(\Rightarrow y_{max}=\frac{9}{4}\) khi \(sinx=\frac{1}{2}\)
\(y=\left(sinx+1\right)\left(2-sinx\right)\)
Do \(-1\le sinx\le1\Rightarrow\left\{{}\begin{matrix}sinx+1\ge0\\2-sinx>0\end{matrix}\right.\)
\(\Rightarrow y=\left(sinx+1\right)\left(2-sinx\right)\ge0\)
\(\Rightarrow y_{min}=0\) khi \(sinx=-1\)
Đúng 0
Bình luận (0)