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imaginary part

American  

noun

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


imaginary part British  

noun

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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of imaginary part

First recorded in 1925–30

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

“Not Forgotten” kicks off imaginary part two, which sees the band setting their phasers to nostalgia and performing as if back in 1990 again, sharing a Madchester stage with The Stone Roses and Happy Mondays.

From Washington Times

Thus, by averaging over many trials and performing a tomographic reconstruction, one can in many cases extract the real and imaginary parts of the full density matrix.

From Nature

These are convoluted mathematical objects that can be analysed using complex numbers - i.e. numbers with real and imaginary parts.

From BBC

Yet let’s remember that z can be any complex number, formed from a real part and an imaginary part: x+iy.

From Scientific American

Note that we have to allow x to admit of all imaginary, as well as of all real, values, in order to obtain all imaginary parts of the locus.

From Project Gutenberg