tangent

Tangent (or tan) is a trigonometric function that gives the ratio between two specific sides of a right-angled triangle.

In a right-angled triangle, one angle is 90° and the other two angles are acute angles.

Label one of the acute angles θ.

The tangent of this angle is the ratio between the length of the side opposite the θ angle and the side between the θ angle and the right angle (the side labelled as adjacent).

The function, therefore, is:

    Tan θ = opposite \div adjacent