Math Basics

All About Numbers

What are imaginary numbers?

The “opposite” of real numbers are (logically enough) called imaginary numbers. In particular, they are all non-zero multiples (real numbers) of the square root of -1, also called i, with the formula defined as follows:


The Image does not have a position on a number line; and no number can be squared to get -1. (If you square a positive number, the result is positive; if you square a negative number, the result is also a positive number.) Thus, in order to square a number to get a negative one, mathematicians invented the imaginary number i.


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