Trigonometry - basics

Front

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

Back

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

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

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

Front

What is the Pythagorean theorem?

Back

In a right triangle, the square of the length of the hypotenuse is equal to the sum of the squares of the lengths of the other two sides: a² + b² = c².

Front

What do the angles in a triangle sum to?

Back

The sum of the angles in any triangle is always 180 degrees.

Front

What is a right triangle?

Back

A right triangle is a triangle that has one angle measuring 90 degrees.

Front

What are the three types of triangles based on angles?

Back

1. Acute triangle (all angles < 90°), 2. Right triangle (one angle = 90°), 3. Obtuse triangle (one angle > 90°).

Front

What is the sine ratio for a 30-degree angle?

Back

The sine of 30 degrees is 1/2.

Front

What is the cosine ratio for a 60-degree angle?

Back

The cosine of 60 degrees is 1/2.

Front

What is the tangent ratio for a 45-degree angle?

Back

The tangent of 45 degrees is 1.