G(x)=3-cosx/2; x=0; x=П/3; x=-П
G(x)=3-cosx/2; x=0; x=П/3; x=-П G(0)=3-cos 0/2=3-1=2 G(п/3)=3-cosп/3/2=3-соsп/6=3-√3/2 G(-п)=3-cos(-п/2)=3