Question

Tan (x) = -2, then Tan(pi + x)= ?

Answer 1

tan ( pi + x ) = - tan x
[This is a rule, because tan z is negative in the 3rd quadrant, (where (pi+x) exists)]

tan x = -2 [given]
\(\therefore\) tan(pi + x) = - ( tan x ) = - (-2) = 2

Answer 2

Woops D:
Tangent is periodic in pi.

So tan( pi + x ) = tan x