Cosine Function
In a trigonometric circle, function f of [latex]\mathbb{R}[/latex] in [latex]\mathbb{R}[/latex] in which all angles of rotation x are made to correspond to the x-coordinate of a point P of the circle.
In the illustration above, cos(x) = h, which is the x-coordinate of point P.
In the illustration above, cos(x) = h, which is the x-coordinate of point P.
Notation
The cosine function is noted as “cos” and the image of an angle of rotation x by this function is written as “cos(x)” and is read as “cosine x” or “cosine of x.”Example
Here is the representation of the basic function defined by the relation f (x) = cos(x):