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

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 LnMcmullin@aol.com 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

Lin McMullin
Richardson, TX

My Blog for calculus teachers: teachingcalculus.wordpress.com

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> -----Original Message-----
> From: erinslong@yahoo.com [mailto:erinslong@yahoo.com]
> --
> 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?
>
>

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