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Topic: [ap-calculus] e
Replies: 1   Last Post: Oct 23, 2012 5:31 PM

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Posts: 10,730
Registered: 12/3/04
RE: [ap-calculus] e
Posted: Oct 23, 2012 5:31 PM
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Calculators and computers are only able to carry a certain number of decimal places (I believe the TI calculators compute with 14 places and round to 12 - something like that). Once past that number the calculator is rounding the (1 +1/x) to 1. Hence the expression looks to the calculator like 1^x. You can see this by calculating (1 + 1/x) for x = 10^12, then 10^13, etc.

It is a "fault" of the technology.


Lin McMullin
Richardson, TX

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I am the moderator of the AP Calculus EDG. I am writing here simply as a member of the EDG. This post is not in any way an "official" announcement from the College Board. When the College Board asks me as the moderator, to share information with you, that e-mail will be clearly marked as being??From the Moderator.??

> -----Original Message-----
> From: []
> --
> So I had a pre calculus student ask me why the lim x->inf (1+1/x)^x is e. I can
> prove it, but I've never noticed until he showed me this that in the calculator,
> the graph of (1+1/x)^x actually goes to one when you plug EXTREMELY large
> numbers into the table values. Does anyone know how to explain this?
> Greatly appreciate your thoughts!

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