2cos^2x-1=sin3x

помогите решить 2+3

cos2x=sin3x

sin3x-sin (π/2-2x) = 0

2sin (5x/2-π/4) cos (x/2+π/4) = 0

sin (5x/2-π/4) = 0⇒5x/2-π/4=πn⇒5x/2=π/4+πn⇒x=π/10+2πn/5

cos (x/2+π/4) = 0⇒x/2+π/4=π/2+πn⇒x/2=π/4+πn⇒x=π/2+2πn

x=π/10; π/2