cos^x+4sin^x-4sinxcosx=0
(cosx-2sinx)^=0
cosx=2sinx
tgx=1/2
x=arctg(1/2)+Пn
cos4x-cos2x=0
-2sin3xsinx=0
sinx=0 x=Пn
sin3x=0 x=Пn/3
cos^x+4sin^x-4sinxcosx=0
(cosx-2sinx)^=0
cosx=2sinx
tgx=1/2
x=arctg(1/2)+Пn
cos4x-cos2x=0
-2sin3xsinx=0
sinx=0 x=Пn
sin3x=0 x=Пn/3