Question

Giúp mình câu 3 với ạ

Answer 1

Do \(\alpha\) nhọn nên \(0<\sin\alpha<1\Rightarrow\sin^{2011}\alpha<\sin^2\alpha\)

Tương tự ta có \(\cos^{2011}\alpha<\cos^2\alpha\)

\(\Rightarrow\sin^{2011}\alpha+\cos^{2011}\alpha<\sin^2\alpha+\cos^2\alpha\)

\(\Rightarrow\sin^{2011}\alpha+\cos^{2011}\alpha<1\)