The chord of the hyperbola `x^(2)/a^(2)-y^(2)/b^(2)=1`, whose equation is `x cos alpha +y sin alpha =p`, subtends a right angle at its centre. Prove that it always touches a circle of radius `(ab)/sqrt(a^(2)-b^(2))`

Answer

coefficient of `x^(2) + ` coefficient of = 0