1. Найдите значения выражений. а) sin(133°)cos(73°)−cos(133°)sin(73°)sin⁡(133°)cos(73°)−cos(133°)sin(73°). - вопрос №113373133731337321024802 от Himop 26.05.2021 09:51

Question

Алгебра: 1. Найдите значения выражений. а) sin(133°)cos(73°)−cos(133°)sin(73°)sin⁡(133°)cos(73°)−cos(133°)sin(73°). б) cos(π14)cos(19π28)−sin(π14)sin(19π28)cos⁡(π14)cos(19π28)−sin(π14)sin(19π28).

Himop · Answer

а) sin(133°)cos(73°)−cos(133°)sin(73°)=sin(133°-73°)=sin60°=(√3)/2 б) cos(π/14)cos(19π/28)−sin(π/14)sin(19π/28)=cos⁡((π/14)+(19π28))=cos(21π/28)==cos(3π/4)=-√2/2...