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## #1 2007-02-09 19:05:33

MathsIsFun

Online

### Imaginary Confusion

You may be familiar with this property of square roots:

For example:

But with imaginary numbers:

Why is this ? ?

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

## #2 2007-02-10 15:41:55

ganesh
Moderator

Offline

### Re: Imaginary Confusion

MathsIsFun,

The square of (-1) is 1. The square root of 1 is ±1. Since the square root of (-1) is represented by i, and it is known that i²=-1, it may be intially baffling that -1=1, but a square root always has two values, positive and negative. In this case, since -1 is also one of the roots, the equation is perfectly right!

Character is who you are when no one is looking.

## #3 2007-02-10 18:04:26

MathsIsFun

Online

### Re: Imaginary Confusion

Awww... I was hoping to cause confusion.

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman