Question

Sin 0 = -3/5
and cos 0 > 0. Identify the quadrant of the terminal side of O and find cos 0.

Answer 1

See below.

Explanation:

Cos O is positive in the first and 4th quadrants and sin O is negative in the 3rd and 4th quadrants.

So the answer is Quadrant 4.

cos^2 O = 1 - sin^2 O

= 1 - (-3/5)^2

= 16/25

So cos O is +√(16/25)

= 4/5.