Clark N. answered 09/09/20
Physics and Mathematics tutor, Harvard-trained with NASA experience
tan(45o) = 1 sin(45o) > 0
tan(135o) = -1 sin(135o) > 0
tan(225o) = 1 sin(225o) < 0
tan(315o) = -1 sin(315o) < 0 Tangent < 0 in quadrants II and IV, sine < 0 in quadrants III and IV, so it's
quadrant IV.