If O is the origin and OP, OQ are distinct tangents to the circle then the circumcentre of the triangle OPQ is
Since PQ is the chord of contact of the tangents from the origin O to the circle
Equation of PQ is
An equation of a circle through the intersection of (i) and (ii) is given by
If the circle (iii) passes through O, the origin, then , i.e., and the equation of the circle (iii)
Centre of this circle is and hence it is the circumcentre of the triangle OPQ.
Study 40% syllabus and score up to 100% marks in JEE