# Sine Function

## Sine Function

In a trigonometric circle, function f of $$\mathbb{R}$$ in $$\mathbb{R}$$ under which all angles of rotation x are made to correspond to the y-coordinate of a point P of this circle.

In the illustration above, sin(x) = k, where k is the y-intercept of point P.

### Symbol

The symbol for the sine function is “sin” and the image of an angle of rotation x of this function is written as “sin(x)” which is read as “sine x” or “sine of x.”
The argument of the function is a number that represents an angle of rotation (and not a figure).

### Example

The graphic representation of the base function defined by f (x) = sin(x), x being the measure of the angle in radians, is: