Question

( frac{0}{a}+cos ^{-1} frac{x}{a}+cos frac{y}{b}=alpha )
LHS
( cos ^{-1}left(frac{x, y}{a^{x} b}-sqrt{frac{1-x^{2}}{a^{2}}}right)^{frac{y^{2}}{b^{2}}}=2 )
( frac{x y}{q b}=cos alpha+sqrt{left(1-frac{x^{2}}{9 y}right)left(1-frac{y^{2}}{b}right)} )
Both sigte square

# XV. If cos-1ă + cos-1= «, show that i hay cosos += =sinoc.

Solution