In a `DeltaABC, if tanA+2tanB=0,` then which one is correct?A. `0lttan – InterviewSolution

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1.	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
Answer» Correct Answer - 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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