Geometry - Chapter 8 (trig) flashcard

Front

What is the definition of the adjacent side in a right triangle?

Back

The adjacent side is the side next to the angle of interest in a right triangle.

Front

What does SOH-CAH-TOA stand for?

Back

SOH-CAH-TOA is a mnemonic for remembering the definitions of sine, cosine, and tangent in a right triangle: Sine = Opposite/Hypotenuse, Cosine = Adjacent/Hypotenuse, Tangent = Opposite/Adjacent.

Front

If the length of the adjacent side is 8 and the hypotenuse is 10, what is the cosine of the angle?

Back

Cosine = Adjacent/Hypotenuse = 8/10 = 0.8.

Front

What is the formula to find the length of a side in a right triangle using the Pythagorean theorem?

Back

The Pythagorean theorem states that a² + b² = c², where c is the hypotenuse and a and b are the other two sides.

Front

How do you find the length of the opposite side if you know the angle and the hypotenuse?

Back

Use the sine function: Opposite = Hypotenuse × sin(angle).

Front

What is the value of sin(30°)?

Back

sin(30°) = 0.5.

Front

What is the value of cos(60°)?

Back

cos(60°) = 0.5.

Front

If the hypotenuse is 21.4 cm and the angle is 30°, what is the length of the opposite side?

Back

Opposite = 21.4 × sin(30°) = 21.4 × 0.5 = 10.7 cm.

Front

What is the tangent of an angle in a right triangle?

Back

Tangent = Opposite/Adjacent.

Front

If the adjacent side is 5 and the opposite side is 5√3, what is the tangent of the angle?

Back

Tangent = Opposite/Adjacent = (5√3)/5 = √3.