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Bernoulli discovered e by studying a question about compound interest

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Re: Bernoulli discovered e by studying a question about compound interest

#11
post #3

Calculus 101? I recall that learning that lim(1 - 1/n)^n with n->inf is 1/e, was one of the first things learned in Calculus. I think we even briefly touched this in highschool.

> I recall that learning that lim(1 - 1/n)^n with n->inf is 1/e

To clarify this should not be 1/e, but e.

Re: Bernoulli discovered e by studying a question about compound interest

#12
post #11
post #3

Calculus 101? I recall that learning that lim(1 - 1/n)^n with n->inf is 1/e, was one of the first things learned in Calculus. I think we even briefly touched this in highschool.

> I recall that learning that lim(1 - 1/n)^n with n->inf is 1/e To clarify this should not be 1/e, but e.

It would be e if there had been a + sign in the parens, but with a - it is, in fact, 1/e. (1-1/n) is always less than 1; multiplying a bunch of factors less than 1 can't possibly* give you 2.something.

*without somehow wrapping around infinity http://en.wikipedia.org/wiki/1_%2B_2_%2B_3_%2B_4_%2B_%E2%80%...

Re: Bernoulli discovered e by studying a question about compound interest

#13

Here's my "e bookshelf" http://imgur.com/YBB33 , which uses the 1/n! definition. It only goes up to 1/3!, but ideally would approach 1/infinity!. e grows as the total area of the clear books on the left. For example, for the bottom shelf, 1/3! is the same as having all possible arrangements of three objects, and choosing one.

Another nice property of the 1/n! definition is that you can use it to define exponentiation for things which don't have division (e.g. matrices)

Re: Bernoulli discovered e by studying a question about compound interest

#15
There is a great book out there called ' Against the Gods ' by Peter Bernstein. http://www.amazon.com/Against-Gods-Remarkable-Story-Risk/dp/... It has the fantastic story of how a lot of mathematical computations are a product of the effort to quantify risk.

Re: Bernoulli discovered e by studying a question about compound interest

#16
post #12
post #11

Earlier quoted context omitted.

> I recall that learning that lim(1 - 1/n)^n with n->inf is 1/e To clarify this should not be 1/e, but e.

It would be e if there had been a + sign in the parens, but with a - it is, in fact, 1/e. (1-1/n) is always less than 1; multiplying a bunch of factors less than 1 can't possibly* give you 2.something. *without somehow wrapping around infinity http://en.wikipedia.org/wiki/1_%2B_2_%2B_3_%2B_4_%2B_%E2%80%...

My mistake, didn't notice the minus sign...
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