From a point A common tangents are drawn to the circle and the parabola y2 = 4 ax. If the area of the quadrilateral formed by the common tangents, the chords of contact of the point A, w.r.t. the circle and the parabola is square unit, then the value of must be
Here, centre of the circle is the vertex of the parabola and both circle and parabola are symmetrical about axis of parabola . in this case the point of intersection of common tangent must lie on the directrix and axis of the parabola.
chord of contact of circle w,r,t is
coordinates of R is and chord of contact of parabola w.r.t is
coordinates of P is (a,2a)
Area of quadrilateral PQRS'