If `cos^(-1)x/a+cos^(-1)y/b=alpha,` prove that `(x^2)/(a^2)-2(x y)/(a b)cosalpha+(y^2)/(b^2)=sin^2alpha`

If cos^(-1)(x/a) + cos^(-1) (y/b) = a show that : (x^2)/(a^2) - (2xy)/(ab) cos alpha + (y^2)/(b^2) = sin^(2) alpha .

If cos^(-1)""x/a+cos^(-1)""y/b=theta , Prove that x^(2)/a^(2)-(2xy)/(ab)costheta+y^(2)/b^(2)=sin^(2)theta .

If cos^(-1) (x/2) + cos^(-1) (y/3) =alpha then prove that 9x^2-12xycosalpha+4y^2=36sin^2alpha .

If cos ^(-1) .(x)/(a)+ cos ^(-1). (y)/(b) = theta then prove that (x^(2))/(a^(2)) -(2xy)/(ab) . cos theta+ (y^(2))/(b^(2)) = sin ^(2) theta .

If cos ^(-1)\ (x)/(a) + cos^(-1)\ (y)/(b) = theta , then (x^(2))/(a^(2)) +(y^(2))/(b^(2))=?

If cos^(-1)x+cos^(-1)y+cos^(-1)z=pi , prove that x^(2)+y^(2)+z^(2)+2xyz=1

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

If cos^(-1)x-cos^(-1)y/2=alpha,t h e n4x^2-4x ycosalpha+y^2 is equal to 4 (b) 2sin^2alpha (c) -4sin^2alpha (d) 4sin^2alpha

If y=(sin^(-1)x)^2+(cos^(-1)x)^2 , then prove that (1-x^2)y_2-xy_(1)-4=0.

If x sin alpha = y cos alpha, prove that : x/(sec 2alpha) + y/(cosec 2 alpha) = x