10.
\(y=3cos2x-5sinx-1\)
\(=3-6sin^2x-5sinx-1\)
\(=-6sin^2x-5sinx+2\)
\(\Rightarrow y=f\left(t\right)=-6t^2-5t+2\) \(\left(t\in\left[-1;1\right]\right)\)
\(\Rightarrow y\in\left[-9;\dfrac{73}{24}\right]\)
\(\Rightarrow y\in\left\{-9;-8;-7;-6;-5;-4;-3;-2;-1;0;1;2;3\right\}\)
....
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