OK, this is simple because it is supposed to be intuitive but I'm just not getting it today. Here is an example: Solve 3tan^2x-1=0 3tan^2x = 1 tan^2x = (1/3) tanx = (+-)(1/sqrt(3)) //All is understood at this point. It's the sentence coming up. Because tan x has a period of pi, first find all solutions in the interval [0, pi). These are x = pi/6 and x = 5pi/6. Ok, I understand the algebra part. But I don't get where the intuitively got x = pi/6?? Could someone explain as my book skips over that step. Thank you in advance.