Noun
(mathematics) a number of the form a+bi where a and b are real numbers and i is the square root of -1
Source: WordNetThis miracle of analysis, this marvel of the world of ideas, an almost amphibian object between Being and Non-being that we call the imaginary number. Gottfried Leibniz
Although the construction is called "imaginary", and although the concept of an imaginary number may be intuitively more difficult to grasp than that of a real number, the construction is perfectly valid from a mathematical standpoint. Source: Internet
If the curve forms a loop, then the only functions whose real part is zero on the curve are those that are everywhere equal to some imaginary number. Source: Internet
If the real part of a complex number is 0, then the number is called an imaginary number or is referred to as purely imaginary; if the imaginary part is 0, then the number is a real number. Source: Internet
The complex numbers also cannot be turned into an ordered field, as −1 is a square (of the imaginary number i) and would thus be positive. Source: Internet
Definition The imaginary number i is defined solely by the property that its square is −1: : With i defined this way, it follows directly from algebra that i and −i are both square roots of −1. Source: Internet