Question

СРОЧНО!!!!!!!!!!!!!!!!

Answer 1

$\displaystyle sin19`*cos19`*2(sin^234`+cos^234`)+cos56`*cos15`=\\\\=2sin19`*cos19`*(1)+\frac{1}{2}(cos(56-15)`+cos(56+15)`)=\\\\=sin2*19`+\frac{1}{2}(cos41`+cos71`)=\\\\=sin38`+\frac{1}{2}(cos41`+cos71`)$