Henry is asked to find the exact value of . His steps are shown below.1. Subtract from as many times as possible: – = 2. Find the reference angle for : – = .3. The cosine value for is .4. The cosine value is positive because is in the first quadrant.Which of the following describes Henry’s errors?
Answer
A
The reference angle should be , and the sign of the value should be negative.
B
The reference angle should be , and the cosine value for is .
C
The sign of the value should be negative, and the reference angle and quadrant should be determined by subtracting in the first step.
D
The cosine value for is , and the reference angle and quadrant should be determined by subtracting in the first step.