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Circles C(1) and C(2) of radii r and R r...

Circles `C_(1)` and `C_(2)` of radii r and R respectively, touch each other as shown in the figure. The lime l, which is parallel to the line joining the centres of `C_(2)` and `C_(2)` is tangent to `C_(1)` at P and intersects `C_(2)` at A,B.If `R^(2)=2r^(2)`, then `angleAOB` equals-

A

`22(1)/(2)@`

B

`45^(@)`

C

`60^(@)`

D

`67(1)/(2)@`

Text Solution

Verified by Experts

The correct Answer is:
B

Chose AB subten `90^(@)` at centre.
so that AB subtend `45^(@)` at O (circumference of circle)
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