Are reference angles also coterminal angles?
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It would seem reference angles end up on the same terminal ray, so wouldn't it be safe to assume that reference angles are also coterminal angles by classification?
Thank You
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$\begingroup$No. The reference angle has the same terminal ray as the original angle, but they may have different starting rays.
In the diagram, $\alpha=\angle AOB$ is the original angle, and $\beta=\angle COB$ is the reference angle. They both have the terminal ray $\overrightarrow{OB}$ but different starting rays. (Note that we consider $\beta$ to be positive, despite its clockwise direction.)
A reference angle is one between $0$ and $90$ degrees that has the same sine, cosine, and tangent in absolute value. It has little to do with coterminal angles.
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