Complement Angles of Sine and Cosine

If cos α = sin β, what must be true about α and β?

• α and β are complementary angles

• α and β are congruent angles

• α and β are right angles

• α and β are supplementary angles

What is the complement to: cos 40⁰ = ?

• sin 50⁰

• cos 50⁰

• tan 50⁰

• sin 40⁰

What is the complement to: sin 20⁰ = ?

• cos 70⁰

• sin 70⁰

• cos 20⁰

• tan 20⁰

What is the complement to: cos 38⁰ = ?

• sin 62⁰

• sin 52⁰

• cos 52⁰

• sin 38⁰

Select all that apply: What is true in respect to the relationship of the sine and cosine of complementary angles? A and B are the acute angles of the right triangle.

What is true in respect to the relationship of the sine and cosine of complementary angles? A and B are the acute angles of the right triangle.

cos 38⁰ = sin θ. What is θ ?

• 62⁰

• 52⁰

• 38⁰

What is true in respect to the relationship of the sine and cosine of complementary angles? A and B are the acute angles of the right triangle.

Select all that apply: What is true in respect to the relationship of the sine and cosine of complementary angles? A and B are the acute angles of the right triangle. 

Sin(60°) = Cos( ?°)

• 10

• 20

• 30

• 40