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In a DeltaABC, if tanA+2tanB=0, then wh...

In a `DeltaABC, if tanA+2tanB=0,` then which one is correct?

A

`0lttan^(2)Cle1/8`

B

`1/8lttan^(2)Cle1/2`

C

`1/2lttan^(2)Clt1`

D

none of these

Text Solution

Verified by Experts

The correct Answer is:
A
We have,
`tanA+2tanB=0`
But in a `DeltaABC`
`tanA+tanB+tanC=tanAtanBtanC`
`implies-2tanB+tanB+tanC=-2tan^(2)B tanC [because tanA=-2tanB]`
`implies2 tan ^(2)BtanC-tanB+tanC=0`
Since the B is real. Therefore, `1-8 tan^(2)c ge0`
`impliestan^(2)Cle1/8lttan^(2)Cle1/8`
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