Use a graphing utility to solve for q, where 0<= q < 2p.

tan q = sqrt( sec²- 1). So we plot the left and right hand sides of the equation as separate functions, then in the same viewing rectangle to see that the funcitons are the same on the intervals 0<= q < p/2, p <= q < 3p/2.

Essential Trigonometry, Math Links

by Jack Tompkins