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# TAN

Returns the tangent of an angle.

## Synopsis

```TAN(number)
```

### Arguments

 number An expression that resolves to a number that specifies an angle in radians.

## Description

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.

By default, Caché MVBasic trig functions return results in degrees. To return results in radians, set \$OPTIONS RADIANS.

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

## Examples

The following example uses the TAN function to return the tangent of an angle:

```Dim MyAngle
MyAngle = 1.3;          ! Define angle in degrees.
Print Tan(MyAngle);     ! Return tangent in radians.
```

The following example uses the TAN function to return the cotangent of an angle:

```Dim MyAngle, MyCotangent
MyAngle = 1.3;                   ! Define angle in degrees.
MyCotangent = 1 / Tan(MyAngle);  ! Calculate cotangent.
Print MyCotangent;               ! Return in radians.```