23" frowe that "cos4x=1-dan^(2)x*cos^(2)x

Prove that cos4x = 2cos^2(2x) - 1

sin^(4)x+cos^(4)x=1-2sin^(2)x cos^(2)x

If (cos ^ (4) x) / (cos ^ (2) y) + (sin ^ (4) x) / (sin ^ (2) y) = 1 then prove that (cos ^ (4) y) / (cos ^ (2) x) + (sin ^ (4) y) / (sin ^ (2) x) = 1

If 2sin x-cos2x=1 ,then (cos^(2)x+cos^(4)x+4)/(2) is equal to

If sin x+sin^(2)x+sin^(3)x=1 then cos^(6)x-4cos^(4)x+8 cos^(2)x=

If sin x + sin^(2) x =1 " then " cos^(8) x + 2 cos^(6) x + cos^(4) x =

Prove that 1+cos2x+cos4x+cos6x=4cosxcos2xcos3x .

Prove that (sin4x+sin2x)/(cos4x+cos2x)=tan3x

Evaluate: int(cos2x sin4xdx)/(cos^(4)x(1+cos^(2)2x))