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Related to imaginary unit: Complex numbers
n. Symbol i
The square root of -1, corresponding to the point (0,1) in the geometric representation of complex numbers as points in a plane.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
the complex number
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