Saved Bookmarks
| 1. |
TanA+tan(60°+A)+tan(120°+A)=3tan3A prove the following |
|
Answer»
apply tan(A+B) formula i.e TANA+tanB /1 -TANATANB tan A + root3 + tanA /1-root3tanA + tan 120 + tanA / 1- tan120tanA
tan(180-60) = -tan60 = -root3 tanA + [root3 + tana / 1-root3tanA ]+ [(-root3) +tanA / 1+root3tanA ] on taking the l.c.m we GET tanA(1- 3tan 2A) +(root3tanA +1)(root3 + tanA) +(tanA -root3)(1-root3tanA )/1-3tan2A after solving brackets we get 9tanA - 3tan3A /1-3tan2A 3(3tanA - tan3A)/1 -3tan2 A i.e 3tan3A HOPE TIS WILL HELP YOU |
|