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# Arctan calculator

## Calculate the arctangent of a number

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Enter the number for which you want to calculate the arctangent below:

## How to calculate an arctangent?

The arctangent of a number is the angle whose tangent is equal to that number. In mathematical terms, if you have a number x and you calculate tan(x), then arctan(tan(x)) is equal to x. The arctangent is often denoted as atan or tan^(-1).

The arctangent is a widely used function in trigonometry, a branch of mathematics dealing with the relationships between the angles and the lengths of the sides of triangles. It is often used to determine the angle of a right-angled triangle, given the lengths of two of its sides.

In JavaScript, the arctangent of a number can be calculated using the built-in function Math.atan(). This function returns the result in radians. To convert the result to degrees, you need to multiply it by 180/π.

It is important to note that, although the tangent of 45 degrees and 225 degrees are both 1, the arctangent of 1 will always be 45 degrees. This is because the Math.atan() function returns a value between -π/2 and π/2 (i.e., -90 and 90 degrees). For angles in other quadrants, you can use the Math.atan2(y, x) function, which returns a value between -π and π, depending on the signs of x and y.

For example, if you want to know the angle between the positive x-axis and the point (x, y), you can calculate it with Math.atan2(y, x).