183k views
3 votes
Check all that apply. Pi/4
is the reference angle for:

User Billygoat
by
7.8k points

1 Answer

5 votes

Reference angle is the angle that is formed by the the terminal side of teh angle and the horizontal line or the x-axis. The reference angles of the different quadrants can be determined using the formula correspondingly:

Quadrant 1: RF = actual angle

Quadrant 2: RF = actual angle - 90 = actual angle - pi/2

Quadrant 3: RF = actual angle - 180 = actual angle - pi

Quadrant 4 : RF = actual angle - 270 = actual angle - 3/4 pi

The first thing to do is to determine the quadrants of each angle and then apply the formula:

a. 19 pi /4 = 855 deg = 2nd Q = 135 + 45 = 180 (correct)

b. 15 pi/4 = 675 deg = 4th Q = 315 + 45 = 360 (correct)

c. 7 pi/4 = 315 deg = 4th Q = 315 + 45 = 360 (correct)

d. 12 pi/4 = 540 deg = x axis = not correct

Answers are A, B and C.

User Luke Givens
by
8.8k points

No related questions found

Welcome to QAmmunity.org, where you can ask questions and receive answers from other members of our community.

9.4m questions

12.2m answers

Categories