Cos2x+cos^2(x-pi/2)=0,75

Question

Cos2x+cos^2(x-pi/2)=0,75

Answer 1

Ответ:

Cos^2(x-90)=sin^x

Cos2x=cos^2x-sin^2x

cos^2x-sin^2x+sin^2x=3/4

cosx=+-sqrt(3)/2

X=+-p/6+2pk