Answer 1

Imaginary numbers are numbers that exist out of the scope of real numbers.
√(-1) does not exist, but this entire field assumes that this has an associated constant that is called i.
Edit (by Haris):
sqrt(-1) doesn't exist within the real numbers.

Answer 2

Imaginary number exist out from the real number

Answer 3

If you imagine the number as a 2D plane with the Real Numbers on the horizontal (x) axis, then the imaginary numbers would be on the vertical (y) axis.
Imaginary is really a poor term that comes from the poor understanding of the numbers from early mathematicians. They are just as real as the "Real Numbers", but they occupy a different space than the Real Numbers.

Answer 4

Imaginary and complex numbers are sometimes used by engineers, scientists and mathematicians but not quite used elsewhere.

Answer 5

a number that is expressed in terms of the square root of a negative number (usually the square root of −1, represented by i or j ).

Answer 6

Imaginary numbers are numbers that does not appear on the real number line. Root of all negative numbers is are imaginary.

Answer 7

real number = number * cos (0) = number
imaginary = number * cos (90) = 0
means if a number is real its not sean by the imaginary axis and vic virsa.
A practical number in coding or real life, has to represent something that is build from various functions or values. if thies valuse are independent from each other you can describe or code it as each one to be imaginary from the other values; where the effect never cross between each other, in math you assign them perpendicular to each other at 90° ~ where you can measure the other value effect on the value that is being calculated by cos (angle deference)