What can complex numbers be used for?

[Wangster]

what are complex numbers used for

I'm a 14 year old computer geek with some interest in math. I've started reading "What is Mathematics?", a tough read, but interesting. So the topic of complex numbers came up and I was wondering what can they be used for?

 

[flatulent]

where are complex numbers used

They are good for AC signals in computing phase and power.

 

[prajit]

what are complex numbers used for?

Please read:
https://www.dspguru.com/info/tutor/QuadSignals.pdf

and also read the Application section of this link

https://en.wikipedia.org/wiki/Complex_number

 

[Lib]

how are complex numbers used

If you want to solve an equation:
a*x^2 + b*x + c = 0,
and (D = b^2 - 4*a*c) < 0,
you can use the complex numbers to get x.

 

[rkodaira]

what is complex numbers used for

In AC circuit analysis, impedances of capacitors and inductors are represented by imaginary numbers (pure resistances are real numbers), which are considered in voltage and current calculations using the DC theory of circuits (ohm law, thevenin, etc) but now represented by complex numbers (as said before, with a module and phase).

 

[spikeyang]

complex numbers uses

Complex numbers are used to describe the two distinct properties of one single object or phenomena, at the same time.

Or maybe the two orthogonal properties in some domain we are most concerned with. Though orthogonal, they may do have some relationships.
For example, postion on a plane , (x,y), they are on the same dimension.

Complex number used in circuit analysis is due to Euler equation. It describe the amplitude and phase of a sinusoidal shape at the same time.

Why not make man + i*woman as the complex number to describe a family?

 

[~E3016~]

complex numbers are used for

i'm usually used it in my study, it is basic for power engineer, in circuit analysis of AC, complex power, inpedance. I just can say that the inventor is greatfull...

 

[Samurai_Neophite]

complx number

When you think of complex numbers think of a polar graph with real on one axis and imaginary on the other. Amplitude/phase, frequency if you imagine cycles/sec- a cycle is 360 degrees. Use a sine to vary imaginary axis and cosine to vary real axis amplitudes, you get a spinning vector which represents a circle and the rate the vector changes is the frequency.

I have another recommendation for you which doesn't have to do with complex #, but throughout life statistics will be thrown at you and it will be used to solve many, many types of problems. A second read for you might be Phillips book "How to think about statistics". It is a good layman's explanation of stats (this is also usually a very tough class).

 

[Yahia Muhammad]

when are comlpex numbers used

complex numbers can be used to represent a lot of physical phenomenas like reactive power impedances etc

 

[IBO]

how to get amplitudes of complex number

complex numbers are used to represent phases

 

[mkhan]

complex numbers are used to calculate what

Hi,

Simply a complex number represents direction and intensity (magnitude) of a quantity. Thats all a complex number is.

BR,

Arif Khan

 

[pelekkk]

where are i numbers used

First of all according to General Algebra Theorem we can find exactly n roots of a n-degree polynomial using complex numbers (and this statement is propably one of the most important things in mathematics ever achieved!). If you're more interested try to find something about Galois Theory, but it's VERY-VERY-EXTREMALY hard (I know what I'm saying, a year ago I've had to pass an Abstract Algebra exam at university. Lib mentined already a 2nd degree polynomial.

Apart from algebra, complex numbers are used to calculate lots of usefull stuff in geometry - a regular geometry you are using everyday For example instead of rotating tiangle 90 degrees left we can multiply it by i I'ts very useful for computers.

Plus of course stuff already mentined

 

[onbssm]

what are complex numbers useful for?

complx numbers are user for reprsent real and imaginary. these are used in electrical theories which are reprent in 2 axis . one is existing we can say real another one is imaginary pary that is use to specify the exact (instantaneous) location of the wave forms

 

[barmak]

what are complex numbers where are they used

well they are used for lots of reasons like for solving lots of math kind of things and they are used in electronic engeenering and they are not that heard trust me
itsnjust like the real number but with some more specialities