To find the arctangent, or inverse tangent, of a number in VBA, we can use the VBA **Atn()** function.

`Atn(x)`

In VBA, we can easily use trigonometric functions from the collection of VBA math functions. These VBA math functions allow us to perform trigonometry easily.

To find the arctangent of a number, we use the VBA **Atn()** function.

Below is the VBA syntax to find the inverse tangent of a number.

`Atn(x)`

The input to the **Atn()** function must be a double. The return value will be a double between -pi/2 and pi/2 radians.

```
Debug.Print Atn(0.5)
Debug.Print Atn(0)
Debug.Print Atn(-0.75)
'Output
0.5235987755982989
0.0
-0.848062078981481
```

## Finding the Inverse Tangent of a Number in VBA

Arctangent is defined as the inverse of the tangent of a number.

Below, we show that if we pass a number to **Tan()** and then call the Excel **Atn()** worksheet function, we get back the same number.

```
Debug.Print Atn(Tan(WorksheetFunction.Pi/3))
Debug.Print WorksheetFunction.Pi/3
'Output:
1.0471975511965976
1.0471975511965976
```

## Find Arc Tangent of the Quotient of Two Arguments with Atan2() in VBA

VBA gives us the ability to find the arctangent of the quotient of two numbers, where the two numbers represents the coordinates of a point (x,y). To find the arctangent of a the quotient of two numbers, we use the atan2() Worksheet Function.

Below is the VBA syntax to find the inverse tangent of the quotient of two numbers.

`WorksheetFunction.Atan2(x)`

The inputs to the **Atan2()** function must be a doubles. The return value will be a numeric value between -pi and pi.

```
Debug.Print WorksheetFunction.Atan2(5,1)
Debug.Print WorksheetFunction.Atan2(0,1)
Debug.Print WorksheetFunction.Atan2(-3,7)
'Output:
1.373400766945016
0.0
-0.40489178628508343
```

Hopefully this article has been beneficial for you to understand how to use the VBA **Atn()** function to find the arctangent of a number.

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