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Let ABC be a triangle and O be its ortho...

Let ABC be a triangle and O be its orthocentre .If R and `R_(1)` are the circum-radii of triangle ABC and AOB , then

A

`R_(1)gtR`

B

`R_(1)=R`

C

`R_(1)ltR`

D

none of these

Text Solution

Verified by Experts

The correct Answer is:
B
In `DeltaAOB`, we have
`angleAOB=A+B`
`thereforeR_(1)=(AB)/(2sin(A+B))rArrR_(1)=c/(2sinC)=R`
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