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Also e**(log(e, e**e)) = 1.444667861009766
and
e**1.444667861009766
converges on e
if you do
e^√1.444667861009766
e^√√1.444667861009766
e^√√√1.444667861009766
etc.
while log(e, 1.444667861009766) = e -
@stop you a mathmatician or familiar with math?
Also, another nifty thing:
(√pi+1)/2 = 1.386226925452758
and
1.386226925452758**0.57721 =
1.2071067811865475
the 0.57721 is a truncation of omega.
now
(√2+1)/2 =
1.2071067811865475
and
1.2071067811865475*2 = 2.414213562373095
which gives you the silver ratio.
I got 1.386226925452758 from
√π^(1/√π) -
stop68045yi know a bit about formulars and how to bring x into one side, since it was a very important part in school, but its my first time with log, but i rember a thing.
-
@stop
Then you still know more than me.
Logs are the reverse of the exponent. You know base 2 vs base 10?
I think it's like that, only you can have any base. -
@stop
it's cool. struggled with this shit at first too.
log(10) = 2.302585092994046
e^2.302585092994046 = 10
e is the 'base' of your logarithm.
Doesn't really explain it. Just know that
You do ln(n) or log(n) = m
and to get your number 'back out'
you do.
e^m = n -
@stop
The base of the outer log is e**(log(p, e**e))
And the base of the inner log is e**e.
Only works for those bases. -
endor56705y@Wisecrack I haven't checked what you're doing, but I can tell you that if your expression works, it can be adapted any base of the logarithm:
log_a (b) = log_c (b) / log_c (a)
Look up logarithm base change for the proof -
@endor
Yeah just noticed that.
I wish I just had a list of identities instead of wasting time making shite half baked wheels. -
endor56705yAlso I just checked the expression you mentioned at the beginning, it is indeed an identity.
You can see that once you figure out that log(p, e^e) = ln(p)/(e * ln(e)) = ln(p)/e -
@endor holyshit, endor, you know your brilliant right?
So what is this maybe useful for?
Is it something new or previously known? -
endor56705y@Wisecrack I'm no genius, I just studied calculus xD.
Exercises like this one (applying the properties of exponentiation/logarithms to evaluate expressions or solve equations) are the first thing you do when studying the topic.
You can find many more like this one in any textbook with exercises - you should try them!
Your expression, in this case, can be simplified in the following way:
log(p, e^(ln(p) / e)) = log(p, p^(1/e))
So p^(1/e) is the base such that log(p, p^(1/e)) = e. This is your original problem statement, and also a slightly more complicated definition of a logarithm.
And if you apply the base change property to that, you'll find:
log(p, p^(1/e)) = ln(p) / ln(p^(1/e)) = ln(p) / (1/e * ln(p)) = e
So, in a very roundabout way, I guess you did what the people who write excercises do: you started from a known identity (log(p, p^(1/e))), applied different properties multiple times, and worked your way up to a more complex expression.
And I had fun solving it :D -
endor56705yAlso I have no idea where you got the p>=5 thing, the analytical expression holds true for any real number p>0. I'm guessing some floating point error got big enough to turn the comparison with e to false?
When evaluating more complex expressions like this one, you typically don't want to do a direct comparison (x == e), but to check if the error is below a small enough threshold (x - e <= 1e-10).
Assuming the numbers you're working with are large enough compared to your threshold, this is an easy way to avoid getting screwed by floats. -
@endor btw I want to thank you endor because had you not mentioned the floating point errors in exponentiation I wouldn't have thought to check for them in my current code.
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This is how to find the base needed for any integer value p, where p>=5, such that the logarithm always equals e in python.
log(p, e**(log(p, e**e))) # equals e
Doesn't do anything besides that but this is another identity isn't?
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