Cos^2(x+п/3) =1 sin^2(x+п/2) =1/2 cos^2(3x-п/4)=3/4

Question

Cos^2(x+п/3) =1
sin^2(x+п/2) =1/2
cos^2(3x-п/4)=3/4

Answer 1

Cos3x=2sin(3pi/2-x)
cos3x=-2cosx
cos3x+2cosx=0
2cos2x*2*(cosx)=0
cos2x или cosx =0
2x=pi/2+Pin      
x=pi/4+Pin/2    x=pi/2+Pin