This guide will explain how to use the IMSIN Function in Google Sheets
Table of Contents
Complex numbers are defined as a combination of a real number and an imaginary number. A complex number’s real and imaginary parts make up an ordered pair that works as coordinates in a two-dimensional complex plane.
Since we’re operating on two dimensions, we often need trigonometric functions when working with complex numbers. If we need to find the sine of a complex number in Google Sheets, we can use the built-in IMSIN
function.
In this guide, we will cover each step you need to start using the IMSIN
function to calculate the sine of a complex number.
The Anatomy of the IMSIN Function
The syntax of the IMSIN
function is as follows:
=IMSIN(number)
Let’s look at each argument to understand how to use the IMSIN
function.
- number refers to the number for which you want to find the sine.
- The number argument can either be a
COMPLEX
function result, a real number, or a string in the format “x+yi” where x and y are valid numbers. - The function will return an error if the number argument is not a valid complex number.
The Anatomy of the COMPLEX Function
The syntax of the COMPLEX
function is as follows:
=COMPLEX(real_part, imaginary_part, [suffix])
Let’s look at each argument to understand how to use the COMPLEX
function.
- real_part refers to the real coefficient of the complex number.
- imaginary_part refers to the imaginary coefficient of the complex number
- suffix is an optional argument where the user can indicate the suffix to use for the imaginary coefficient. By default, the value for this argument is “i”.
A Real Example of Using the IMSIN Function
Let’s explore a few simple examples where we’ll need to use the IMSIN
function in Google Sheets.
Using a cell reference
We can use the IMSIN
function to find the sine given a cell reference as input.
Suppose we have a complex number in cell A2. We can determine the sine using the following formula:
=IMSIN(A2)

In the example above, we used the IMSIN
function and found that the sine of the complex number 3+2i is 0.53092108624852-3.59056458998578i.
Using the COMPLEX function
If only the coefficients of the complex number are given, we’ll need to use the COMPLEX
function to produce a valid complex number for the IMSIN
function.

In the example above, we have a table with the coefficients of our complex numbers’ real and imaginary parts. We can use the following formula to get the sine given the two coefficients:
=IMSIN(COMPLEX(A2,B2))

Using this formula, we were able to find the sine values given a set of real and imaginary coefficients.
Click on the link below to create your own copy of our examples.
Head to the next section to read our step-by-step tutorial on how to start using the IMSIN
function in Google Sheets.
How to Use the IMSIN Function in Google Sheets
- Select the cell where you want to output the sine.
- Type the
IMSIN
function and add the target complex number as an argument. You can either write down a complex number written in the form “a+bi” or a cell reference to a valid complex number.In this example, we’ll use the formula IMSIN(A2) to find the sine value of the complex number 3+2i.
- Hit the Enter key to evaluate the
IMSIN
function. - Use the AutoFill feature to find the sine result of the remaining complex numbers in the dataset.
- When given the coefficients of the complex number, use the
COMPLEX
function to output a valid complex number.In our table above, we’ll use the formula IMSIN(COMPLEX(A2,B2)). The
COMPLEX
function is used inside theIMSIN
function to convert the coefficients 3 and 2 into the valid complex number 3+2i.
These steps are all you need to know to start using the IMSIN
function in Google Sheets.
FAQs
- Why is my IMSIN function returning an error?
TheIMSIN
function may return an error for a variety of reasons. Ensure that the complex number you’re using as an argument is in the proper format a+bi. If your complex number is missing the imaginary unit suffix, your function may result in an error. - How do I find the other trigonometric functions given a complex number?
Google Sheets includes several other functions to help you perform trigonometric functions on complex numbers. You can use theIMCOS
function to find the cosine of a complex number and theIMTAN
function to find the tangent of a complex number.
To learn more about using Google Sheets to work with complex numbers, you can read our guide on how to find the natural logarithm of a complex number.
That’s all for this guide! Be sure to check out our library of spreadsheet resources, tips, and tricks!
