If Cos-1 ( (x/2) ) + Cos-1 ( (y/3) ) = θ, then 9x2 - 12 xy cos θ + 4 y2 =

Question

If Cos-1 ( (x/2) ) + Cos-1 ( (y/3) ) = θ, then 9x2 - 12 xy cos θ + 4 y2 =  (A) 36 sin2 θ (B) 37 sin2 θ (C) 39 sin2 θ (D) 36 cos2 θ

Tardigrade Admin · Accepted Answer

Correct answer is (a) 36 sin2 θ

Q. If $C o s^{- 1} (\frac{x}{2}) + C o s^{- 1} (\frac{y}{3}) = θ$ , then $9 x^{2} - 12 x y cos θ + 4 y^{2} =$