Question

Помогите решить
√8-√32sin²$frac{11pi}{8}$

Answer 1

$2 sqrt{2}-4 sqrt{2} *sin^2 frac{11 pi }{8}=2 sqrt{2} (1-2sin^2 frac{11 pi }{8}) \ 1-2sin^2 alpha =cos2 alpha \ 2 sqrt{2} * cos frac{11 pi }{4}=2 sqrt{2} * (- frac{ sqrt{2} }{2} )=-2$