Question

Вычислить a) sin75; б)cos32*cos2°+sin32*sin2° ; в) sin95*cos5°-cos95*sin5°

Answer 1

а) sin(75) = sin(30+45) = sin(30)cos(45) + sin(45)cos(30) = (1/2)(√2/2) + (√2/2)(√3/2) = √2/4 + √6/4 =  (√2 + √6)/4
б) cos(32)cos(2) + sin(32)sin(2) = cos(32-2) = cos(30) = √3/2
в)sin(95)cos(5) - cos(95)sin(5) = sin(95-5) = sin(90) = 1