If cos θ= 1/4and 0
If cos θ= 1/4and θ is between 0 and 90, find tan θ
cos^2 + sin^2 = 1
1/16 + sin^2 = 1
sin^2 = 15/16 sin = sqrt15 /4
tan = sin / cos = sqrt15/4 /1/4 = sqrt 15