Question

Tan 7pi/12

Answer 1

\[\tan(\frac{ 7 \pi }{ 12 })\]
yes?
so what do you wish to accomplish with this? find the exact value? etc..

Answer 2

Ya

Answer 3

Find the exact value

Answer 4

7pi/15 = 105 deg
so 105 = 90+15
tan (90+x) = - cot x
so tan 105 = tan(90+15)=cot 15
so try finding tan 15.....
which is tan (45-30) = (tan 45 - tan 30) / (1 + tan 45 tan 30)
= (1-tan 30)/(1+tan 30)
So cot 15 = 1/tan 15 = (1+tan 30)/(1-tan 30)
So tan 105 = - (1+tan 30)/(1-tan 30)
and tan 30 = sqrt(3) = 1.732.... now rest is solved by a simple substitution...and done!!