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The chord of contact of tangents from a point `P` to a circle passes through `Qdot` If `l_1a n dl_2` are the length of the tangents from `Pa n dQ` to the circle, then `P Q` is equal to `(l_1+l_2)/2` (b) `(l_1-l_2)/2` `sqrt(l1 2+l2 2)` (d) `2sqrt(l1 2+l2 2)`

A

`(l_(1)+l_(2))/(2)`

B

`(l_(1)-l_(2))/(2)`

C

`sqrt((l_(1)^(2)+l_(2)^(2)))`

D

`sqrt((l_(1)^(2)-l_(2)^(2)))`

Text Solution

Verified by Experts

The correct Answer is:
C
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