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## #1 2011-08-11 02:29:27

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,835
Website

### Log

If Log p + Log q= Log (p+q)

Then what is the relationship between p & q?

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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## #2 2011-08-11 02:35:58

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Log

Hi;

I am getting:

Take the exponential of both sides.

There may be other solutions!

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #3 2011-08-11 03:17:52

bob bundy
Registered: 2010-06-20
Posts: 8,108

### Re: Log

hi Agnishom and bobbym,

What bobbym has said holds good whatever log base you are using providing all three logs are the same base throughout the equation.

Furthermore, as log is an increasing function I think bobbym's answer is the only one.

Bob

ps. also providing neither p nor q is equal to 1.

Last edited by bob bundy (2011-08-11 03:19:52)

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #4 2011-08-12 01:01:54

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,835
Website

### Re: Log

What may b othr answers

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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## #5 2011-08-12 01:08:37

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

### Re: Log

Hi;

Some guy wrote:

There may be other solutions!

Bob does not think there are any others ( he has a point ) and I can not find any others. Maybe that statement was too cautious.

In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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## #6 2013-03-06 19:38:07

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,835
Website

### Re: Log

bobbym wrote:

How did you get rid of e on the second line RHS

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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## #7 2013-03-06 20:17:14

bob bundy
Registered: 2010-06-20
Posts: 8,108

### Re: Log

hi Agnishom

There are two rules being used here.

and

Bob

Last edited by bob bundy (2013-03-06 23:16:49)

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #8 2013-03-06 21:40:42

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,037

### Re: Log

Hi Bob

The LaTeX command for that is \Leftrightarrow.

Here lies the reader who will never open this book. He is forever dead.
Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

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## #9 2013-03-06 21:55:14

bob bundy
Registered: 2010-06-20
Posts: 8,108

### Re: Log

Thanks Stefy,

I thought that was what I typed but maybe not.

Bob

Last edited by bob bundy (2013-03-06 23:17:11)

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #10 2013-03-06 21:56:41

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,037

### Re: Log

You need a big L to get the equivalence arrow.

Here lies the reader who will never open this book. He is forever dead.
Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

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## #11 2013-03-06 23:17:33

bob bundy
Registered: 2010-06-20
Posts: 8,108

### Re: Log

Thanks again.

Bob

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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## #12 2013-03-06 23:19:32

anonimnystefy
Real Member
From: Harlan's World
Registered: 2011-05-23
Posts: 16,037

### Re: Log

You are welcome!

Here lies the reader who will never open this book. He is forever dead.
Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment
The knowledge of some things as a function of age is a delta function.

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## #13 2013-03-07 01:55:12

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,835
Website

### Re: Log

I understand now
Thanks bob bundy

Isn't thinkng about e a redundancy over here?

'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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