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## #1 2012-10-22 15:36:17

Leroy
Guest

### Logarithm

Can one do logarithm of imaginery number?please explain.

## #2 2012-10-22 18:47:44

bob bundy
Moderator

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### Re: Logarithm

hi Leroy,

Yes you can.  See

http://en.wikipedia.org/wiki/Complex_logarithm

Bob

You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

## #3 2012-10-22 22:30:27

Leroy
Guest

### Re: Logarithm

There is no example in that link,it will be great if you show an example

## #4 2012-10-22 22:54:23

bobbym

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### Re: Logarithm

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

## #5 2012-10-22 23:01:50

Leroy
Guest

### Re: Logarithm

So,let me try, is this correct
ln(3+4i)=ln5+atan(4/3)i

## #6 2012-10-22 23:12:21

bobbym

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### Re: Logarithm

Hi;

That is correct. Very good!

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Leroy
Guest

Thank you a lot.

## #8 2012-10-23 02:37:23

bobbym

Offline

### Re: Logarithm

Hi;

You are welcome!

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.