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How to Use the IMAGINARY Function

How to Use the IMAGINARY Function in Excel

The IMAGINARY function is used to extract the imaginary coefficient of a complex number.

Contents:


Syntax

= IMAGINARY(complex_number)

complex_number - This is the complex number for which you want to find the absolute value. It can be supplied as a string (like "3+4i") or as a reference to a cell containing the complex number.


Explanation

The IMAGINARY function is part of the "Engineering" group of functions within Excel.


This function is used to extract the imaginary part of a complex number.


Complex Number Format

A complex number is usually in the form 'a + bi' or sometimes 'a + bj', where a is the real part or coefficient, b is the imaginary part, and i or j is the imaginary number or unit.


So, in the complex number '9+3i', the imaginary coefficient would be 3.


Examples

How to Extract the Imaginary Coefficient of a Complex Number

Let's say we have table with complex numbers, and need to pull out the imaginary components of each number.

How to Extract the Imaginary Coefficient of a Complex Number in excel

Without the IMAGINARY function, we would have to use a complicated formula to extract the imaginary part of each cell. But, with the IMAGINARY function, we can simply type:

= IMAGINARY(A2)

To extract the imaginary coefficient from a complex number held in cell A2.


So if we put that formula alongside our table and reference the complex numbers, we get something that looks like this:

How to Extract the Imaginary Part of a Complex Number in Excel

Here, with the IMAGINARY formula in the second column, we can see that the imaginary parts of each complex number are returned correctly, including the + and - signs and decimals.

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