What's the point of imaginary numbers? They don't exist, right?

Answer 1

I know its just as bad as beein as to find X when there it is on the page. LOL

Answer 2

Numbers are man's doing. We all take it for granted, but we have to undersand that numbers are our creation, and it just an assumption. Do you know how difficult people in the ancient times found it to even imagine the zero?
An alien may have a completely different "number" system. 1+1 =2
WHo told you that? Man made the decision that 1 sheep plus another sheep gives him 2.
I sound like a moron, dont I? Then think about this.

You say imaginary numbers dont exist.
Why didnt you think about negative numbers? Do they exist?
They dont.
What about positive numbers? Yeah they exist, but what is existence mean for these numbers.

you can never decide if numbers exist or not, its all in your head.

but we take it for granted.

Math is just the usage of numbers, to do certain calculations, and these calculations give us the right result all the time.

The number line is a straight line. People were not satisfied with it. So they pulled it to 2 dimensions. Hence imaginary numbers. Now stretch it to 3 dimensions. Crap, right?


Think about this: A man and a woman go inside an empty room. Three people come out a year later. Does that mean another person should go in to make the room empty?

Answer 3

I answered this question several days ago. I can give you two very practical applications.
1. Scientists have found that the internal structure of the atom is governed by an equation with an imaginary number in it, although I forget the name of this equation.
2. Some problems in electronics can be done without complex numbers but take pages of algebra to solve. If imaginary numbers (strictly speaking complex numbers) are introduced at the beginning and then removed later the problem can be done in a few lines.

Answer 4

What's The point of learning about negative numbers? They don't exist either, right? Afterall, when have you ever seen negative objects? My point is that "imaginary" number is a misnomer. If you walk 3 ft in East direction and turn around and walk -3 ft backwards the sum of -3+3=0 which means you are back at where you started. Imaginary just like backtracking can be thought of as a rotation. In trig you would have learned y axis is imaginary axis. Hence rotate 90° and is same as multiplying your directional coordinates by i

Answer 5

Imaginary numbers are used to describe vectors that have length & direction.
i.e. j if you have a vector of unit 1 operating at 0 degrees and it is multiplyed by j it becomes 1j it is still unit 1 but now it is operating at 90 degrees.
If a vetor unit 1 is operating at 45 degrees then it can be described as 1+j .
mulitply unit 1 vector @ 0 degrees by j^2 then it becomes -1 @ 180 degrees

Answer 6

Imaginary numbers appear in AC circuits.

Answer 7

Despite their name, imaginary numbers are as "real" as real numbers. One way to understand this is by realizing that numbers themselves are abstractions, and the abstractions can be valid even when they are not recognized in a given context. For example, fractions such as ⅔ and ⅛ are meaningless to a person counting stones, but essential to a person comparing the sizes of different collections of stones. Similarly, negative numbers such as − 3 and − 5 are meaningless when keeping score in a US football game, but essential when keeping track of monetary debits and credits (or yards gained on a play in the same football game).

Imaginary numbers follow the same pattern. For most human tasks, real numbers (or even rational numbers) offer an adequate description of data, and imaginary numbers have no meaning; however, in many areas of science and mathematics, imaginary numbers (and complex numbers in general) are essential for describing reality. Imaginary numbers have essential concrete applications in a variety of sciences and related areas such as signal processing, control theory, electromagnetism, quantum mechanics, cartography, and many others.

For example, in electrical engineering, when analyzing AC circuitry, the values for the electrical voltage (and current) are expressed as imaginary or complex numbers known as phasors. These are real voltages that can cause damage/harm to either humans or equipment even if their values contain no "real part". The study of AC (alternating current) entails introduction to electricity governed by trigonometric (i.e. oscillating) functions. From calculus, one knows that differentiating or integrating either "+/- sin(t)" or "+/- cos(t)" four times (with respect to "t," of course) results in the original function "+/- sin(t)" or "+/- cos(t)." From complex algebra, one knows that multiplying the imaginary unit quantity "i" by itself four times will result in the number 1 (identity). Thus, calculus can be represented by the algebraic properties of the imaginary unit quantity (this was exploited by Charles Proteus Steinmetz).

Specifically, Euler's formula is used extensively to express signals (e.g., electromagnetic) that vary periodically over time as a combination of sine and cosine functions. Euler's formula accomplishes this more conveniently via an expression of exponential functions with imaginary exponents. Euler's formula states that, for any real number x,


Some programming languages also have built-in support for imaginary numbers. For example, in the Python interpreter, one may use them by appending a lowercase or uppercase J to the number:

>>> (5+2j) * (8+5j)
(30+41j)

Answer 8

Its just a way of expressing numbers in 2 dimensions. They are used them quite a bit to solve equations in engineering.

Answer 9

I've got a good imagination and I can't think for the life of me what imaginary numbers are, please explain??