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**RauLiTo****Member**- From: Bahrain
- Registered: 2006-01-11
- Posts: 142

it seems easy but not for a beginner like me in logs !

can anyone prove that :

log4^3 > log5^3

ImPo$$!BLe = NoTH!nG

Go DowN DeeP iNTo aNyTHinG U WiLL FinD MaTHeMaTiCs ...

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,922

If 2³ = x, then log x (to the base2) is equal to 3.

However, log4^3<log 5^3,

Since 4^3 = 64 and 5^3 = 125

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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**RauLiTo****Member**- From: Bahrain
- Registered: 2006-01-11
- Posts: 142

excuse me mr.ganesh can u explain that more ?

please understand it i am just a beginner in logs !

ImPo$$!BLe = NoTH!nG

Go DowN DeeP iNTo aNyTHinG U WiLL FinD MaTHeMaTiCs ...

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,922

Hi RauLiTo,

we know 1000=10³ ,

hence, log(1000) to the base 10 = 3.

Logarithms are calculated for the two bases, e and 10.

Logarithm to base e is called Natural logarithm and logarithm to base 10 is common logarithm. Go to this link for knowing more.

Logarithms help in calculating approximately quickly.

For example, by knowing what log 2(to the base 10) is, it can easily be said how large a number 2^100 would be!

If you have any specific doubts or problems, you may post here.

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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**RauLiTo****Member**- From: Bahrain
- Registered: 2006-01-11
- Posts: 142

Moderator ganesh thank you very very much ... can you accept to add me in ur list ?

i hope its okay to put my e-mail in this forum (( i am sorry if that is not allowed )) thanks again man

*Last edited by ganesh (2006-02-24 00:09:20)*

ImPo$$!BLe = NoTH!nG

Go DowN DeeP iNTo aNyTHinG U WiLL FinD MaTHeMaTiCs ...

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**ganesh****Moderator**- Registered: 2005-06-28
- Posts: 20,922

Thats nice to hear, RauLiTo

Since a lot of kids visit the forum, posting your e-mail is generally not permitted. You can visit the forum often, post your messages, play games,make friends and try solving the puzzles.

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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