A variable tangent to the parabola y^2 = 4ax meets the circle x^2 + y^2 = r^2 at P and Q. Prove that the locus of the midpoint of PQ is x( x^2 + y^2) +ay^2 = 0
A variable tangent to the parabola y^2 = 4ax meets the circle x^2 + y^2 = r^2 at P and Q. Prove that the locus of the midpoint of PQ is x( x^2 + y^2) +ay^2 = 0