СРОЧНО Sin4x-cos^4x=-sin^4x
Sin4x=cos^4x-sin^4x sin4x=(cos²x-sin²x)(cos²x+sin²x) sin4x=cos2x 2sin2xcos2x-cos2x=0 cos2x*(2sin2x-1)=0 cos2x=0⇒2x=π/2+πk⇒x=π/4+πk/2,k∈z 2sin2x=1 sin2x=1/2 2x=π/6+2πk U 2x=5π/6+2πk,k∈z x=π/12+πk U x=5π/12+πk,k∈z