On the unit circle, where 0 less-than theta less-than equal to 2 pi, when is tangent theta undefined?
Theta = pi and Theta = 2 pi
sine theta = cosine theta
Theta = StartFraction pi Over 2 EndFraction and Theta = StartFraction 3 pi Over 2 EndFraction
sine theta = StartFraction 1 Over cosine theta EndFraction