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#1 2011-08-12 00:29:27

Agnishom
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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'
'Who are you to judge everything?' -Alokananda

#2 2011-08-12 00:35:58

bobbym
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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.
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.

#3 2011-08-12 01:17:52

bob bundy
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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 (2011-08-12 01:19:52)


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

#4 2011-08-12 23:01:54

Agnishom
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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'
'Who are you to judge everything?' -Alokananda

#5 2011-08-12 23:08:37

bobbym
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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.
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.

#6 2013-03-07 18:38:07

Agnishom
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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'
'Who are you to judge everything?' -Alokananda

#7 2013-03-07 19:17:14

bob bundy
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Re: Log

hi Agnishom

There are two rules being used here.



and



Bob

Last edited by bob bundy (2013-03-07 22:16:49)


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

#8 2013-03-07 20:40:42

anonimnystefy
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Re: Log

Hi Bob

The LaTeX command for that is \Leftrightarrow.


The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

#9 2013-03-07 20:55:14

bob bundy
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Re: Log

Thanks Stefy,

I thought that was what I typed but maybe not.



Bob

Last edited by bob bundy (2013-03-07 22:17:11)


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

#10 2013-03-07 20:56:41

anonimnystefy
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Re: Log

You need a big L to get the equivalence arrow.


The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

#11 2013-03-07 22:17:33

bob bundy
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Re: Log

Thanks again.

Bob


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

#12 2013-03-07 22:19:32

anonimnystefy
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Re: Log

You are welcome!


The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

#13 2013-03-08 00:55:12

Agnishom
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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'
'Who are you to judge everything?' -Alokananda

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