Right Triangle Trig Flashcard

Front

What is the definition of sine (sin) 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 (cos) 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 (tan) 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

What does SOH-CAH-TOA stand for?

Back

SOH-CAH-TOA is a mnemonic to remember the definitions of sine, cosine, and tangent: SOH = Sine = Opposite/Hypotenuse, CAH = Cosine = Adjacent/Hypotenuse, TOA = Tangent = Opposite/Adjacent.

Front

If sinA = 4/5, what is the length of the opposite side if the hypotenuse is 20?

Back

The length of the opposite side is 16 (4/5 of 20).

Front

If cosB = 3/5, what is the length of the adjacent side if the hypotenuse is 25?

Back

The length of the adjacent side is 15 (3/5 of 25).

Front

What is the Pythagorean theorem?

Back

The Pythagorean theorem states that in a right triangle, the square of the length of the hypotenuse (c) is equal to the sum of the squares of the lengths of the other two sides (a and b): a² + b² = c².

Front

How do you find the length of the hypotenuse if the lengths of the other two sides are 9 and 12?

Back

Use the Pythagorean theorem: c = √(9² + 12²) = √(81 + 144) = √225 = 15.

Front

What is the value of tan(45°)?

Back

The value of tan(45°) is 1.

Front

If the opposite side is 5 and the adjacent side is 12, what is the value of tanA?

Back

tanA = Opposite/Adjacent = 5/12.