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7th June 2004, 10:36 #1
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difference between log and log to the base 10
HI
can any one explain me difference between natural log and log of base ten.
Thanks

7th June 2004, 14:54 #2
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natural log of pi
A number can be represented by a first number raised to the exponent of a second number. The second number is call the logarithm and the first number is the base. The two most common bases are 10 and 2.7......
The symbol for the first is Log and for the second Ln.

7th June 2004, 14:54

7th June 2004, 21:15 #3
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differnece between ln and log
the reson of choosing 10 is obvious, but why e=2.7...?
the answer is that it back to 300 years or more ago. to Euler (which e comes from his name). the function e^x is the only function that its derivative (and consequently its integral) is itself. {e^x'=e^x). no other function has this charasteristic. the number e could be achieved by several numerical and analytical methods, more often infinite summations.
this number has more important rule in complex analysis.
marti

7th June 2004, 21:15

10th June 2004, 12:52 #4
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difference between natural log and log of base ten
And if you need to convert between them:
log10(x) = ln(x) / ln(10)
ln(x) = log10(x) / log10(e)

10th June 2004, 12:52

10th June 2004, 13:12 #5picusGuest
Re: difference between natural log and log of base ten
y
y = log (x) ==>find y: x = b
b
where b is the base (b = 10 or b = e)

12th July 2004, 11:28 #6
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Re: difference between natural log and log of base ten
Thanks for your interesting reply. I did not realise the e comes from Euler's name until I real your post!
By the way, does anybody know any history of the pi (3.14)?
Originally Posted by mamali

12th July 2004, 11:47 #7
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Re: difference between natural log and log of base ten
Originally Posted by no
http://www.wordiq.com/definition/Pi
http://www.campusprogram.com/referen...a/p/pi/pi.html
http://www.briantaylor.com/Pi.htm
There 100's of pages like this, no need to ask about it here.

4th December 2005, 04:02 #8
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Re: difference between natural log and log of base ten
virology.wisc.edu/acp/Classes/ DropFolders/DropBioMod_lectures/M04NatLogs.pdf
there u go

4th December 2005, 04:02

8th May 2006, 07:42 #9
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Re: difference between natural log and log of base ten
By the way, does anybody know any history of the pi (3.14)?
The ratio of circumference to diameter is pi.
Note that pi=22/7 is just an approximation,thats why it not a rational but irrational number

8th May 2006, 18:35 #10
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difference between natural log and log of base ten
You should read:
e: The Story of a Number
by Eli Moar
for a more historical and detailed discussion.
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