Question

2cos^2х-cos 2х упростить

Answer 1

2cos^2 x - cos 2x = 2cos^2 x - (cos^2 x - sin^2 x) = cos^2 x + sin^2 x = 1

Answer 2

$2cos^2x-cos2x=2cos^2x-cos^2x+sin^2x=cos^2x+sin^2x=1$