Question

Найдите значение выражения. Тригонометрия. 9 класс

Answer 1

(2cos45*cos40+2sin45*cos30);(4√2*1/2(sin50+sin60))=
=2*√2/2(cos40+√3/2):(2√2(cos40+√3/2))=1/2

Answer 2

$frac{cos5+cos85+sin75+sin15}{4 sqrt{2}cos5sin55 }= frac{2cos45*cos40+2sin45*cos30}{4 sqrt{2} frac{1}{2} (sin50+sin60)}=\\= frac{ sqrt{2}(cos40+ frac{ sqrt{3} }{2}) }{2 sqrt{2}(cos40+ frac{ sqrt{3} }{2} ) } =1/2$