3cos2x-sin^2 x+cos^2 x=2cos2x

Question

3cos2x-sin^2 x+cos^2 x=2cos2x

Answer 1

3cos2x-sin^2 x+cos^2 x=2cos2x

3cos2x+cos^2 x-sin^2 x=2cos2x

3cos2x+cos2x-2cos2x=0

2cos2x=0

cos2x=0

2x=pi/2+pik . k=z

x=pi/4+2pik/2 . k=z