NTA Abhyas JEE Main2020MathematicsCirclePractice
Let P Q and R S be the tangents at the extremities of the diameter P R of a circle of radius r . If P S and R Q intersect at a point X on the circumference of the circle, then the value of 2 r is equal to
Options
- APQ · RS
- BPQ + RS 2
- C2 PQ · RS PQ + RS
- DPQ 2 + RS 2 2
Correct answer
A. PQ · RS
Step-by-step solution
From the figure, it is clear that Δ PRQ and Δ RSP are similar. ∴ PR RS = PQ RP ⇒ PR 2 = PQ · RS ⇒ PR = PQ · RS ⇒ 2 r = PQ · RS