If `(cos^(4)x)/(cos^(2)y)+(sin^(4)x)/(sin^(2)y)=1`, then `(cos^(4)y)/(cos^(2)x)+(sin^(4)y)/(sin^(2)y)` equal :

If (cos^(2)x + 1/(cos^(2) x)) (1+tan^(2) 2y) (3+ sin 3z)=4 , then

If y = (cos^(2))(3x)/(2) - (sin^(2))(3x)/(2) , then (d^(2)y)/(dx^(2)) is

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

The value of (cos^(4)x+cos^(2)x sin^(2) x + sin^(2)x)/(cos^(2)x+ sin^(2) x cos^(2) x + sin^(4)x) is ____________

cos ^(2) 2x -cos ^(2) 6x = sin 4x sin 8x

If sin x+sin ^(2) x=1 then the value of cos ^(2) x+cos ^(4) x is

Prove that cos^(2)2x-cos^(2)6x=sin4x.sin8x ?

int (4)/(sin^2 x cos^(2) x)dx is equal to :

(cos x + cos y ) ^(2) + (sin x - sin y ) ^(2) = 4 cos ^(2) ""(x + y )/( 2)