Returns a **Double** specifying the tangent of an angle.

**Syntax**

**Tan(**
**
number
**

**)**

The required ** number**argument is a Double or any valid numeric expression that expresses an angle in radians.

**Remarks**

**Tan** takes an angle and returns the ratio of two sides of a right triangle. The ratio is the length of the side opposite the angle divided by the length of the side adjacent to the angle.

To convert degrees to radians, multiply degrees by pi/180. To convert radians to degrees, multiply radians by 180/pi.

## Example

**Note:** Examples that follow demonstrate the use of this function in a Visual Basic for Applications (VBA) module. For more information about working with VBA, select **Developer Reference** in the drop-down list next to **Search** and enter one or more terms in the search box.

This example uses the **Tan** function to return the tangent of an angle.

```
```Dim MyAngle, MyCotangent

MyAngle = 1.3 ' Define angle in radians.

MyCotangent = 1 / Tan(MyAngle) ' Calculate cotangent.