On the unit circle, the coordinates of a 270° angle are (0, -1).
At this point x-value = 0, y-value = -1, r-value (the distance from the origin to the point) = 1.
sin = y/r cos = x/r tan = y/x csc = r/y sec = r/x cot = x/y
sin(270°) = -1/1 = -1 csc(270°) = 1/-1 = -1
cos(270°) = 0/1 = 0 sec(270°) = 1/0 = undefined
tan(270°) = -1/0 = undefined cot(270°) = 0/-1 = 0