If `cos^(-1)(x/m)+cos^(-1)(y/n)=theta`, then `x^2/m^2-(2xy)/(mn)costheta+y^2/n^2` is equal to

If Cos^(-1)(x/a)+Cos^(-1)(y/b)=theta,"then "x^(2)/a^(2)-(2xy)/(ab)costheta+y^(2)/b^(2)=

cos^(-1)(x//a)+cos^(-1)(y//b)=theta ,then (x^(2))/(a^(2))-(2xy)/(ab)cos theta+(y^(2))/(b^(2))=

If "cos"^(-1)(x/a) ="cos"^-1(y/b) = theta, "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 , 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)=theta then the maximum of 9x^(2)-12xy costheta + 4y^(2) is

If cos^(-1)(x)/(2)+cos^(-1)(y)/(3)=theta then the maximum of 9x^(2)-12xy costheta + 4y^(2) is

If cos^(-1)x+cos^(-1)y=theta show that x^(2)-2xy cos theta+y^(2)=sin^(2)theta