imaginary part

American  

noun

Mathematics.

1. the coefficient b in the complex number a + bi.

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imaginary part British  

noun

1. the coefficient b in a complex number a + i b , where i = √–1

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Etymology

Origin of imaginary part

First recorded in 1925–30

Example Sentences

Phoenix was imaginary, part of a 2009 government preparation exercise for a killer hurricane dubbed Project Phoenix — an exercise updated in 2020 focusing on small business recovery.

From Seattle Times • Sep. 27, 2022

Let’s consider the number The real part of the complex number is and the imaginary part is We plot the ordered pair to represent the complex number as shown in Figure 1.

From Textbooks • Dec. 1, 2021

Let’s consider the number The real part of the complex number is and the imaginary part is 3.

From Textbooks • Feb. 13, 2015

These complex numbers can be plotted on an ordinary graph, with the real part marked along the x axis and the imaginary part on the y axis.

From Scientific American • Sep. 26, 2012

The horizontal axis represents the real part of the complex number, while the vertical axis represents the imaginary part.

From "Zero: The Biography of a Dangerous Idea" by Charles Seife