sin(x+п/6)+cos(x+п/3)=1+cos2x

Question

sin(x+п/6)+cos(x+п/3)=1+cos2x

Answer 1

cosx=1+cos2x

cosx=1+2cos^2x-1

cosx-2cos^2x=0

cosx(1-2cosx)=0

1)cosx=0 x=90градусов

2)cosx=1/2 x=60градусов