ATAN - Excel - Microsoft Office Online

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ATAN

Applies to: Microsoft Office Excel 2003

Returns the arctangent, or inverse tangent, of a number. The arctangent is the angle whose tangent is number. The returned angle is given in radians in the range -pi/2 to pi/2.

Syntax

ATAN (number)

Number is the tangent of the angle you want.

Remark

To express the arctangent in degrees, multiply the result by 180/PI( ) or use the DEGREES function.

Example

The example may be easier to understand if you copy it to a blank worksheet.

Show How to copy an example

Create a blank workbook or worksheet.
Select the example in the Help topic.
Note Do not select the row or column headers.

Selecting an example from Help
Press CTRL+C.
In the worksheet, select cell A1, and press CTRL+V.
To switch between viewing the results and viewing the formulas that return the results, press CTRL+` (grave accent), or on the Tools menu, point to Formula Auditing, and then click Formula Auditing Mode.

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A	B
Formula	Description (Result)
=ATAN(1)	Arctangent of 1 in radians, pi/4 (0.785398)
=ATAN(1)*180/PI()	Arctangent of 1 in degrees (45)
=DEGREES(ATAN(1))	Arctangent of 1 in degrees (45)