Sine, Cosine, or Tangent

Front

What is the definition of sine in a right triangle?

Back

Sine (sin) is the ratio of the length of the opposite side to the length of the hypotenuse.

Front

What is the definition of cosine in a right triangle?

Back

Cosine (cos) is the ratio of the length of the adjacent side to the length of the hypotenuse.

Front

What is the definition of tangent in a right triangle?

Back

Tangent (tan) is the ratio of the length of the opposite side to the length of the adjacent side.

Front

If sin Z = 15/17, what is the value of cos Z?

Back

Using the Pythagorean identity, cos Z = √(1 - sin²Z) = √(1 - (15/17)²) = 8/17.

Front

What is the Pythagorean identity for sine and cosine?

Back

sin²θ + cos²θ = 1.

Front

How do you find the value of cos X if you know sin X?

Back

Use the Pythagorean identity: cos X = √(1 - sin²X).

Front

What is the relationship between sine and cosine for complementary angles?

Back

sin(90° - θ) = cos(θ).

Front

If cos 75° is needed to solve for x, what is the next step?

Back

Divide both sides by cos 75°.

Front

What is the value of cos 60°?

Back

cos 60° = 1/2.

Front

What is the value of sin 30°?

Back

sin 30° = 1/2.