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#1 2006-03-29 10:04:14

MathsIsFun
Registered: 2005-01-21
Posts: 7,664

Logarithm Formulas

Logarithm Formulas

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

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#2 2006-04-01 17:52:46

ganesh
Registered: 2005-06-28
Posts: 23,306

Re: Logarithm Formulas

If

then

because

It is no good to try to stop knowledge from going forward. Ignorance is never better than knowledge - Enrico Fermi.

Nothing is better than reading and gaining more and more knowledge - Stephen William Hawking.

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#3 2006-04-04 04:11:31

Ricky
Moderator
Registered: 2005-12-04
Posts: 3,791

Re: Logarithm Formulas

Last edited by Ricky (2006-04-04 04:11:44)

"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

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#4 2006-08-05 13:53:15

Zhylliolom
Real Member
Registered: 2005-09-05
Posts: 412

Re: Logarithm Formulas

Logarithm of a Complex Number

where k is an integer.

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#5 2006-08-05 19:03:45

Devantè
Real Member
Registered: 2006-07-14
Posts: 6,400

Re: Logarithm Formulas

(which is log(xy) = log x + log y)

Last edited by Devanté (2006-08-05 19:10:52)

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#6 2006-09-05 03:15:28

Devantè
Real Member
Registered: 2006-07-14
Posts: 6,400

Re: Logarithm Formulas

Last edited by Devanté (2006-10-06 23:23:57)

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#7 2006-10-10 00:22:34

Devantè
Real Member
Registered: 2006-07-14
Posts: 6,400

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#8 2009-01-02 06:03:12

random_fruit
Member
Registered: 2008-12-25
Posts: 39

Re: Logarithm Formulas

Can anyone explain Devante's post #7?  He says

This does not make sense to me, and seems to me to have exactly one value of x for which it is true.

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#9 2009-04-19 18:30:04

Shekhar
Member
Registered: 2009-04-19
Posts: 1

Re: Logarithm Formulas

Can anyone prove the following....
Given,
((2/3)^k)n = 1
Required to prove,
k is equal to log of n on base 3/2

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#10 2009-04-19 19:39:47

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

Re: Logarithm Formulas

Hi random_fruit;

It could be a quiz problem and I agree it appears  to have only 1 solution in R.

Last edited by bobbym (2009-04-19 19:44:38)

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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#11 2009-06-09 21:04:36

noobard
Member
Registered: 2009-06-07
Posts: 28

Re: Logarithm Formulas

ganesh wrote:

If

then

because

hey ganesh jus a little thing
if we take  A and B of the same signs

here it should be

..

and in the other ones also... the argument has to be alwys positive

Everything that has a begining has an EnD!!!

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#12 2009-11-25 23:06:46

sekhar5955
Member
Registered: 2009-11-25
Posts: 1

Re: Logarithm Formulas

Hi Shekhar,
Here is the solution.
((2/3)^k)n = 1
⇒(2/3)^k = 1/n
⇒(2/3)^k = n-¹
Applying log on both sides.
⇒k log(2/3) = -log n
Multiplying (-) on both sides
⇒k log(2/3)-¹ = log n
⇒k log(3/2) = log n
∴ k = (log n)/(log (3/2))
⇒ k = log n base (3/2)

Shekhar wrote:

Can anyone prove the following....
Given,
((2/3)^k)n = 1
Required to prove,
k is equal to log of n on base 3/2

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