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How to find the reference angle for any angle not on the unit circle

Answer 1

Abigail Nelson

Charlotte Davis

To find the reference angle for an angle θ not on the unit circle, you must first locate the angle in the appropriate quadrant. The reference angle is then the smallest angle between the terminal side of θ and the x-axis. Here are the steps:

1. If θ is in the first quadrant, the reference angle is θ itself:

$ θ_{ref} = θ $

2. If θ is in the second quadrant, the reference angle is:

$ θ_{ref} = 180° – θ $

3. If θ is in the third quadrant, the reference angle is:

$ θ_{ref} = θ – 180° $

4. If θ is in the fourth quadrant, the reference angle is:

$ θ_{ref} = 360° – θ $

Answer 2

Alex Thompson

Daniel Carter

To find the reference angle for an angle θ not on the unit circle:

1. If θ is in the first quadrant, the reference angle is θ:

$ θ_{ref} = θ $

2. If θ is in the second quadrant, the reference angle is:

$ θ_{ref} = 180° – θ $

3. If θ is in the third quadrant, the reference angle is:

$ θ_{ref} = θ – 180° $

4. If θ is in the fourth quadrant, the reference angle is:

$ θ_{ref} = 360° – θ $

Answer 3

Amelia Mitchell

Chloe Evans

To find the reference angle for an angle θ not on the unit circle:

1. First quadrant: $ θ_{ref} = θ $

2. Second quadrant: $ θ_{ref} = 180° – θ $

3. Third quadrant: $ θ_{ref} = θ – 180° $

4. Fourth quadrant: $ θ_{ref} = 360° – θ $