Question

упростите выражения(10-11 класс)

Answer 1

1)2$cos^{2}$x-cos2x
cos2x=2$cos^{2}$x-1
2$cos^{2}$x-2$cos^{2}$x+1=1
2)cos2x+2$sin^{2}$x=
cos2x=1-2$sin^{2}$x=
1-2$sin^{2}$x+2$sin^{2}$x=1