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

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

If cos^(-1)(x/2)+cos^(-1)(y/3) = theta , prove that 9x^2- 12xycostheta+ 4y^2= 36 sin^(2)theta

If cos^(-1)((x)/(2))+cos^(-1)((y)/(3))=theta, prove that 9x^(2)-12xy cos theta+4y^(2)=36sin^(2)theta

If cos^(-1)x//2+cos^(-1) y//3=theta," prove that "9x^(2)-12xy cos theta+4y^(2)=36sin^(2) theta

If "cos"^(-1)(x/y) +"cos"^-1(y/3)= theta, "prove that" 9x^2- 12xy "cos" theta +4y^2 =36 "sin"^2 theta .

If "cos"^(-1) x/(2)+"cos"^(-1) y/(3)=theta , then prove that 9x^(2)-12xy " cos "theta+4y^(2)=36" sin "^(2)theta

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

If cos ^(-1) ""(x)/(2) + cos ^(-1) "" (y)/(3) = theta, then prove that 9x ^(2) - 12 xy cos theta + 4y ^(2) = 36 sin ^(2) theta

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