Coaxial System

Q. The lengths of tangents from a fixed point to three circles of coaxial system are $t_1,t_2,t_3$ and if P, Q and R be the centres, then $QR{t}_1^2+RP{t}_2^2+PQ{t}_3^2$ is equal to

1. 1
2. 2
3. 3
4. \N

Q.

The point (2, 3) is a limiting point of a coaxial system of circles of which $x^2+y^2=9$ is a member. The co-ordinates of the other limiting point is given by

1. $(\frac{18}{13},\frac{27}{13})$

2. $(\frac{9}{13},\frac{6}{13})$

3. $(\frac{18}{13},-\frac{27}{13})$

4. $(-\frac{18}{13},-\frac{9}{13})$