Special Right Triangles and Sohcahtoa Precalculus

What Greek letter is often used to represent an acute angle of a right triangle?

• Delta

• Alpha

• Theta

• Beta

Answer explanation

Which trigonometric function is the opposite over the hypotenuse?

• Tangent

• Sine

• Cosine

• Secant

Answer explanation

Sine is written as sin(x).

Which trigonometric function is the adjacent over the hypotenuse?

• Tangent

• Sine

• Cosine

• Secant

Answer explanation

Cosine is written as cos(x).

Which trigonometric functions is the opposite over the adjacent?

• Tangent

• Sine

• Cosine

• Secant

Answer explanation

Tangent is written as tan(x).

Match each trigonometric function to their reciprocal.

• Cosecant

• Tangent

• Cotangent

• Cosine

• Secant

• Sine

Answer explanation

Cosecant is written as csc(x), secant is written as sec(x), and cotangent is written as cot(x).

Write the memory device that is used to remember the three trigonometric functions. (Use only capital letters, with hyphens in between each set, like ABC-DEF-GHI.)

Answer explanation

SOH-CAH-TOA stands for sine-opposite-hypotenuse, cosine-adjacent-hypotenuse, tangent-opposite-adjacent.

Which side is the hypotenuse?

• AB

• BC

• CA

Answer explanation

The hypotenuse is the side directly across from the right angle.

Which side is the opposite?

• AB

• BC

• CA

Answer explanation

The opposite is the side opposite from the reference angle, which is in this case the theta.

Which side is the adjacent?

• AB

• BC

• CA

Answer explanation

The adjacent is the side next to the reference angle, which is in this case the theta.

This is a 45, 45, 90 degree triangle. Which two sides would be marked with an L?

• AB

• BC

• CA

Answer explanation

L can be replaced with any variable.