Learn =ATAN() function – How to use with examples

The ATAN function in Excel returns the arctangent (inverse tangent) of a given number. It is a mathematical function that can be used to find the angle whose tangent is equal to the given number.

How to use ATAN() function in Excel:

To use the ATAN function in Excel, follow these steps:

  1. Select the cell where you want to display the result.
  2. Type the following formula into the formula bar: =ATAN(number), where “number” is the value for which you want to find the arctangent.
  3. Press Enter to calculate the result.
  4. The result will be displayed in the selected cell.

Here are examples of using the ATAN() function in Excel:

  1. =ATAN(1) returns 0.785398163 (radians)
  2. =ATAN(-1) returns -0.785398163 (radians)
  3. =ATAN(0) returns 0 (radians)
  4. =ATAN(2) returns 1.107148718 (radians)
  5. =ATAN(0.5) returns 0.463647609 (radians)
  6. =ATAN(1/2) returns 0.463647609 (radians)
  7. =ATAN(10/5) returns 1.107148718 (radians)
  8. =ATAN(PI()) returns 1.262627255 (radians)
  9. =ATAN(SQRT(3)) returns 1.047197551 (radians)
  10. =ATAN(1/SQRT(3)) returns 0.523598776 (radians)

List of Similar Functions:

  • TAN: Returns the tangent of an angle.
  • ATAN2: Returns the arctangent of the specified x- and y-coordinates.
  • ATANH: Returns the inverse hyperbolic tangent of a number.
  • ACOT: Returns the arccotangent of a number.

FAQs for Use of ATAN Function in Excel

What is the domain and range of the ATAN function in Excel?

The domain of the ATAN function is all real numbers and the range is between -pi/2 and pi/2 radians.

Can the ATAN function return an error?

Yes, the ATAN function can return the #NUM! error if the input value is outside the domain of the function.

Can the ATAN function return a negative value?

Yes, the ATAN function can return a negative value if the input value is negative.

How do I convert the result of the ATAN function to degrees?

To convert the result of the ATAN function from radians to degrees, use the DEGREES function.

What is the difference between the TAN and ATAN functions?

The TAN function returns the tangent of an angle, while the ATAN function returns the arctangent of a number.

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