1) cos^2(x)-cos(2x)=sin(x)
cos^2(x)-(cos^2(x)-sin^2(x))=sin(x)
sin^2(x)-sin(x)=0
sin(x)(sin(x)-1)=0
a) sin(x)=0
x=pi*n
б) sin(x)-1=0
sin(x)=1
x=(pi/2)+2*pi*n
2) cos(2x)+sin^2(x)=cos(x)
( cos^2(x)-sin^2(x))+sin^2(x)=cos(x)
cos^2(x)-cos(x)=0
cos(x)(cos(x)-1)=0
a) cos(x)=0
x=(pi/2)+pi*n
б) cos(x)-1=0
cos(x)=1
x=2*pi*n
