Help with Trig function graphs?

Question

How do you graph 4tanx?

I need to be able to do this without the use of a graphing calculator.

Answer 1

4 tan 0 = 0

Place symptotes at π/2 + nπ

Period is π

4 tan π/4 = 4

4 tan -π/4 = -4

 

Sketch graph.

Answer 2

First, set the function equal to zero to find the roots.  Second, substitute x for zero to find the y-intercept.