Trigonometry Functions 11

Question

Evaluate exactly and provide a diagram for each to support your answer. Do not use your calculator.

a) cos 210° = b) tan 315° = c) sin 240° = d) cos(-270)

Answer 1

a) cos210 = -cos30 = -sqr3/2

b)tan315 = -tan45 = -1

c) sin240 = -sin60 = -sqr3/2

d) cos(-270) = cos90 = 0

a) is in the 3rd quadrant

b) in the 4th quadrant

c) in 3rd quadrant

d) is the borderline between 1st & 2nd quadrants