In order for tan x = 0, sin x must be = 0 <span>sin x = 0 at 0 degrees and 180 degrees </span> <span>so, tan x = 0 at 0, pi </span> <span>as for the period being pi, you need to have tan x be negative and positive </span> <span>so remember the acronym All students take calculus ( ASTC) for where they are positive. </span> <span>tan x is negative in Quadrant II and positive in Quadrant I, since it just repeats after that, the period therefore must be Pi.</span>
