Question

помогите плиз (сos п/12+sin п/12)^2

Answer 1

$(cosfrac{pi}{12}+sinfrac{pi}{12})^2=cos^2frac{pi}{12}+2sinfrac{pi}{12}cosfrac{pi}{12}+sin^2frac{pi}{12}=\(sin^2frac{pi}{12}+cos^2frac{pi}{12})+sin(2*frac{pi}{12})=1+sinfrac{pi}{6}=1+frac{1}{2}=frac{3}{2}=1,5.$