Друзья надо! 1. 2sin3x- √3=0, 2. 2 sin ²+ 5 cosx-4=0, 3. 2sin²*x/3-5sin*x/3 +3cos² * x/3=0, 4.cos3x=2sin*(3π/2 +x) 5. 5sin2x-2sinx=0 6.1+cosx=cos x/2 7. 1-cos²2x=sin3x-cos(π/2 +x) 8.1+sin9x=(sin x/2 - cos x/2)²

2sin3x=k3

sin3x=k3/2

3x=(-1)^k p/3+pn

x=(-1)^k p/9+pn/3 

5sin2x-2sinx=0 

10sinxcosx-2sinx=0

2sinx(5cosx-1)=0

2sinx=0  sinx=0   x=pn

5cosx-1=0   cosx=1/5    x=arccos(1/5)+2pk

1+cosx-cosx/2=0 

2cos^2 x/2 -cosx/2=0

cosx/2(2cosx/2-1)=0

cosx/2=0  x/2=p/2+pn  x=p+2pn

2cosx/2=1  cosx/2=1/2  x/2=p/3+2pn   x=2p/3+4pn