Right Triangle Trigonometry Basics

Front

Sine (sin)

Back

A trigonometric function representing the ratio of the length of the opposite side to the hypotenuse in a right-angled triangle.

Front

Cosine (cos)

Back

A trigonometric function representing the ratio of the length of the adjacent side to the hypotenuse in a right-angled triangle.

Front

Tangent (tan)

Back

A trigonometric function representing the ratio of the length of the opposite side to the adjacent side in a right-angled triangle.

Front

Opposite Side

Back

The side opposite the reference angle (theta) in a right triangle.

Front

Adjacent Side

Back

The side next to the reference angle (theta) in a right triangle.

Front

Theta, Alpha, Beta

Back

Variables used to represent angles in trigonometry.

Front

Hypotenuse

Back

The longest side of a right-angled triangle, opposite the right angle.

Front

Cofunction Identity

Back

In any right triangle, the sine of one of the acute angles will always equal the cosine of the opposite acute angle.