Summary

The Excel IMSUM function returns the sum of two or more complex numbers.

Purpose 

Get sum of complex numbers

Return value 

Sum of complex numbers as text

Syntax

=IMSUM(inumber1,[inumber2],...)
  • inumber1 - Complex number 1.
  • inumber2 - [optional] Complex number 2.

How to use 

The Excel IMSUM function returns the sum of two or more complex numbers. For example:

=IMSUM("4+3i","2-5i") // returns "6-2i"

Excel handles complex numbers as strings formatted like “x+yi” or “x+yj”. Use the COMPLEX function to get the string representing a complex number.

Examples

The IMSUM function takes in two or more arguments in the form inumber1, inumber2, inumber3, and so on. Arguments can be hard-coded values, cell references, or a range. Use the IMSUM function in a range like this:

=IMSUM(B6:B10) // sum complex numbers in B6:B10

If Excel encounters values not recognized as complex numbers, a #NUM! Error is thrown.

=IMSUM("4+3i", "invalid input") // throws #NUM! error

Explanation

The sum of two complex numbers is visualized by arranging the arrows tip-to-tail and drawing an arrow from the origin to the tip of the second number. For example, the sum of "4+3i" and "2-5i" is visualized below, where the arrow "6-2i" is the sum of the complex numbers.

Visualization of complex addition by adding the arrows representing complex numbers tip-to-tail together.

Image courtesy of wumbo.net.
 

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Dave Bruns

Hi - I'm Dave Bruns, and I run Exceljet with my wife, Lisa. Our goal is to help you work faster in Excel. We create short videos, and clear examples of formulas, functions, pivot tables, conditional formatting, and charts.