Question

How do you evaluate `tan (120)`?

Answer 1

Evaluate tan (120)
Ans: `- sqrt3`

Explanation:

1. Trig table of special arcs --> `tan 120 = -sqrt3`

2. `tan 120 = tan (150 - 30) = (tan (150 - tan 30)/(1 + tan 30.tan.60) =`
   `= (-sqrt3/3 - sqrt3/3)/[1 + (-sqrt3/3)(sqrt3/3)] =`
   `= ((-2)(sqrt3/3))/((1 - 1/3)) = ((-2sqrt3)/3)(3/2) = -sqrt3`