Basic Trigonometry

Front

What is the definition of sine (sin) in a right triangle?

Back

In a right triangle, sine (sin) of an angle 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

In a right triangle, cosine (cos) of an angle 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

In a right triangle, tangent (tan) of an angle 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 = Sin = Opposite/Hypotenuse, CAH = Cos = Adjacent/Hypotenuse, TOA = Tan = Opposite/Adjacent.

Front

If sin(30) = ?

Back

sin(30) = 1/2.

Front

If cos(60) = ?

Back

cos(60) = 1/2.

Front

If tan(45) = ?

Back

tan(45) = 1.

Front

How do you find the height (h) using cosine?

Back

Use the formula: cos(angle) = adjacent/hypotenuse. Rearranging gives h = hypotenuse * cos(angle).

Front

What is the relationship between the sides in a 30-60-90 triangle?

Back

In a 30-60-90 triangle, the sides are in the ratio 1:√3:2.

Front

What is the Pythagorean theorem?

Back

In a right triangle, the square of the hypotenuse (c) is equal to the sum of the squares of the other two sides (a and b): c² = a² + b².