# log(x) or ln(x)

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#1
The title sums it up.
http://www.strawpoll.me/20217873
1
5 months ago
#2
log(x) and ln(x) mean the same thing as far as I know.
0
5 months ago
#3
log(X) usually means a log with base 10 whereas ln(X) means a lot with base e
2
5 months ago
#4
(Original post by jamiet0185)
log(X) usually means a log with base 10 whereas ln(X) means a lot with base e
Both log(x) and ln(x) denote the natural logarithm.

It's very rare to find log(x) to mean log base 10.
1
5 months ago
#5
(Original post by Mihaly)
Both log(x) and ln(x) denote the natural logarithm.

It's very rare to find log(x) to mean log base 10.
Perhaps it is, although I'm pretty sure it's base 10 if you use the log button on a calculator?
0
5 months ago
#6
Not sure what the point of this is.

As it stands, it really depends on your area of expertise. Across all of mathematics, the norm is that and both denote the natural logarithm, because base 10 is completely inconvenient. If we really do intend to mean base 10, we either define it as so at the beginning of our work, or just write .

Whereas if you go into some sort of area like engineering, then will always refer to base 10 logarithm, because real-life measurements are in the base-10 system and so it is very much convenient in this context.
Last edited by RDKGames; 5 months ago
1
5 months ago
#7
log is almost unanimously used to mean the natural logarithm in maths. In some cases it might also denote the base-2 logarithm. It will be clear from context.
1
5 months ago
#8
(Original post by Mihaly)
Both log(x) and ln(x) denote the natural logarithm.

It's very rare to find log(x) to mean log base 10.
It's because pocket calculators were designed for engineers and the like!
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#9
Some of yall are reading into something that isn't there.
I'm just curious what notation people prefer.
0
5 months ago
#10
(Original post by anon2.718)
Some of yall are reading into something that isn't there.
I'm just curious what notation people prefer.
It's not really a matter of preference is it?
It's a matter of context.
4
5 months ago
#11
(Original post by Mihaly)
log(x) and ln(x) mean the same thing as far as I know.
Log(x) would imply base 10
Whereas ln(x) implies natural log or base e
0
5 months ago
#12
(Original post by BuryMathsTutor)
It's not really a matter of preference is it?
It's a matter of context.
PRSOM

(Original post by anon2.718)
Some of yall are reading into something that isn't there.
I'm just curious what notation people prefer.
I'm a mathematician, so I really don't care. Though the A-Level days have drilled it into me to use , hence it stuck around.
Last edited by RDKGames; 5 months ago
0
5 months ago
#13
(Original post by mnot)
Log(x) would imply base 10
Whereas ln(x) implies natural log or base e
In pure maths, log is usually unmistakably the natural logarithm. (unless context suggests otherwise)

In applied areas, it might be a bit more ambiguous, so ln might be used. (some places, eg. proofwiki use ln everywhere to avoid ambiguity)
0
5 months ago
#14
(Original post by _gcx)
In pure maths, log is usually unmistakably the natural logarithm. (unless context suggests otherwise)

In applied areas, it might be a bit more ambiguous, so ln might be used. (some places, eg. proofwiki use ln everywhere to avoid ambiguity)
Fair.
This is just what I thought it was from my A-level days.

As an engineer I pretty much just use ln for everything
Last edited by mnot; 5 months ago
0
5 months ago
#15
(Original post by RDKGames)
Not sure what the point of this is.

As it stands, it really depends on your area of expertise. Across all of mathematics, the norm is that and both denote the natural logarithm, because base 10 is completely inconvenient. If we really do intend to mean base 10, we either define it as so at the beginning of our work, or just write .

Whereas if you go into some sort of area like engineering, then will always refer to base 10 logarithm, because real-life measurements are in the base-10 system and so it is very much convenient in this context.
At A level there is a distinction.
1
5 months ago
#16
(Original post by Muttley79)
At A level there is a distinction.
Which part of this thread suggests that OP has asked this question in the context of A-Level studies, and not beyond?
0
5 months ago
#17
(Original post by anon2.718)
The title sums it up.
http://www.strawpoll.me/20217873
For A level, it is usual to use ln for log to the base e and log to be log to the base 10 -
0
5 months ago
#18
(Original post by RDKGames)
Which part of this thread suggests that OP has asked this question in the context of A-Level studies, and not beyond?
You've assumed - so I thought I should clarify. It might have been helpful to specify the level you were talking about?
0
5 months ago
#19
(Original post by Muttley79)
You've assumed - so I thought I should clarify. It might have been helpful to specify the level you were talking about?
A general question should receive a general outlook. No need to assume anything more specific.
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#20
(Original post by BuryMathsTutor)
It's not really a matter of preference is it?
It's a matter of context.
I mean in a context where log(x) and ln(x) are interchangeable, i.e. a math context.
0
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