If `cos^(-1) x - cos^(-1). y/2= alpha ", then " 4x^(2) - 4xy cos alpha + y^(2) ` is equal to

If cos^(-1) x - cos ^(-1) (y)/(2) =alpha then 4x^(2) -4xy cos alpha+ y^(3) is equzal to

If cos^(-1)x-"cos"^(-1)y/2=alpha , then 4x^(2)-4xycos alpha+y^(2) is equal to

If cot^(-1)x-"cos"^(-1)(y)/(2)=alpha , then 4x^(2)-4xy cos alpha+y^(2) is equal to :

If cos^(-1)x- cos^(-1)""(y)/2 = alpha , then 4x^2 -4xycos alpha +y^2 is equal a) 2 sin alpha b)4 c) 4 sin^2alpha d) -4 sin^2alpha

If Cos^(-1)x-Cos^(-1)(y/2)=alpha" then "4x^(2)-4xycosalpha+y^(2)=

If cos^(-1)x-cos^(-1)y=alpha, then x^(2)+y^(2)-2xy cos alpha is equal to

If cos^(- 1)x-cos^(- 1)(y/2)=alpha then 4x^2-4xycosalpha+y^2=

If cos^(- 1)x-cos^(- 1)(y/2)=alpha then 4x^2-4xycosalpha+y^2=

If "cos"^(-1) x/a +"cos"^(-1) y/b=alpha , then : x^2/a^2 -(2xy)/(ab) cos alpha + y^2/b^2 equals :