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# Let y^{2} = 4ax be parabola and PQ be a focal chord of parabola. Let T be the point of intersection of tangents at P and Q. Then

- area of circumcircle of ΔPQT is
- orthocenter of ΔPQT will lie on tangent at vertex.
- incenter of ΔPQT will be vertex of parabola.
- incentre of ΔPQT will lie on directrix of parabola.

## The correct answer is: area of circumcircle of ΔPQT is

for focal chord t_{1}t_{2} = – 1

Tangent drawn at the extremities of focal chord are perpendicular and meet at directrix

= 90º

Hence PQ is diameter of circum circle of ΔPTQ.

2r = PQ r = (PQ/2)

Area of circum circle =

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