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In triangle A B C ,/C=(2pi)/3 and C D is...

In triangle `A B C ,/_C=(2pi)/3` and `C D` is the internal angle bisector of `/_C ,` meeting the side `A Ba tD` . If Length `C D` is `1,` the H.M. of `a and b` is equal to:

A

1

B

2

C

3

D

4

Text Solution

Verified by Experts

The correct Answer is:
B
`CD = (2ab)/(a+b) cos.(C)/(2) = (2ab)/(a+b) cos.(pi)/(3) = (ab)/(a+b) = 1`
`:. (2ab)/(a+b) = 2`
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