Question

The angle 01 is located in Quadrant II, and sin(01) =

9/41
What is the value of cos(01)?
Express your answer exactly.
cos(01) =

Answer 1

-40/41

Explanation:

Since we know 'cos' involves the Adjacent and Hypoteneus sides, we will need to solve for the 'Adjacent' side of the triangle using the Hypoteneus Theorem.

41² = 9² + a²

a = 40.

However, this is in quadrant II, so when finding the 'cos' value, this side is -40.

Cosine is A/H, giving is:

cos(01) = -40/41