Question

\(y=\sqrt{4-3\sin2x}-1\)

Answer 1

\(Vì-1\le\sin2x\le1\)

\(\Rightarrow3\ge-3\sin2x\ge-3\)

\(\Rightarrow-3\le-3\sin2x\le3\)

\(\Rightarrow1\le4-3\sin2x\le7\)

\(\Rightarrow\sqrt{1}\le\sqrt{4-3\sin2x}\le\sqrt{7}\)

\(\Rightarrow0\le\sqrt{4-3\sin2x}-1\le\sqrt{7}-1\)

\(\Rightarrow0\le y\le\sqrt{7}-1\)

\(Vậy\) \(y_{max}=\sqrt{7}-1\)

        \(y_{min}=0\)