Flashcard: Coterminal and Reference Angles

Front

What is a coterminal angle?

Back

Coterminal angles are angles that share the same terminal side when drawn in standard position. They can be found by adding or subtracting multiples of 360° (or 2π radians).

Front

How do you find a reference angle?

Back

A reference angle is the acute angle formed by the terminal side of an angle and the x-axis. To find it, subtract the angle from 180° (or π radians) if the angle is in the second quadrant, or subtract 360° (or 2π radians) if in the fourth quadrant.

Front

Back

Tags

CCSS.HSF.TF.C.9

Front

What is sin 45°?

Back

Tags

CCSS.HSG.SRT.C.6

Front

What can we say about the angle and the reference angle?

Back

They add up to 180 degrees.

Front

Back

Yes, they are coterminal angles.

Front

What is the reference angle for an angle of 138°?

Back

The reference angle is 42°.

Front

What is the sine of 30°?

Back

Tags

CCSS.HSG.SRT.C.6

Front

What is the cosine of 60°?

Back

Tags

CCSS.HSG.SRT.C.7

Front

What is the tangent of 45°?

Back

The tangent of 45° is 1.

Tags

CCSS.HSG.SRT.C.7