уравнение: 2 sin^2 x + cos 5x = 1

Question

уравнение:

2 sin^2 x + cos 5x = 1

Answer 1

cos5x=cos2x

cos5x-cos2x=-2sin3,5xsin3/2x=0

sin3x/2=0

3x/2=Пk

x=2Пk/3

sin7x/2=0

7x/2=Пk

x=2Пk/7