Flashcard: Right Triangle Trigonometry

Front

What is the definition of sine 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 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 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

Evaluate sin 39°.

Back

0.63

Front

Evaluate cos 57°.

Back

0.54

Front

Evaluate tan 90°.

Back

Undefined (tan 90° approaches infinity).

Front

What is the Pythagorean theorem?

Back

In a right triangle, a² + b² = c², where c is the hypotenuse.

Front

If one angle of a right triangle is 30°, what is the sine of that angle?

Back

sin 30° = 0.5.

Front

If one angle of a right triangle is 45°, what is the cosine of that angle?

Back

cos 45° = √2/2 or approximately 0.71.

Front

What is the relationship between the angles in a right triangle?

Back

The sum of the angles in a right triangle is always 180°, with one angle being 90°.