Sine, Tangent, and Cosine

How to calculate Sine

Opposite/Hypotenuse

Sine

Sin, or sine, is short for "sine of an angle." It's a ratio that describes the relationship between the length of the side opposite an angle in a right triangle and the length of the triangle's hypotenuse (the longest side).

Cosine

Cos, or cosine, is short for "cosine of an angle." It's another ratio that describes the relationship between the length of the side adjacent to an angle in a right triangle and the length of the hypotenuse.

How to calculate Cosine

Adjacent/hypotenuse

How to calculate tangent

Opposite/adjacent

What is Tangent

Tan, or tangent, is short for "tangent of an angle." It's a ratio that describes the relationship between the length of the side opposite an angle in a right triangle and the length of the side adjacent to that angle

When to use Sine, Cosine, and Tangent

In simpler terms, sin, cos, and tan can be thought of as tools to help you find missing sides or angles in a right triangle. You use sin when you know the length of the opposite side and the hypotenuse, cos when you know the length of the adjacent side and the hypotenuse, and tan when you know the length of the opposite and adjacent sides.