Author Topic: CIE P3 doubt ~  (Read 1310 times)

Offline eightAs

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CIE P3 doubt ~
« on: January 01, 2010, 02:56:14 pm »
I just came across a proof for the derivate of e^x being e^x itself.There was one part of the proof I couldn't understand. Why would the following equation hold:
limit \tiny\ x \tiny\rightarrow 0 (\LARGE\frac{e^x - 1}{x})  = 1.
« Last Edit: January 01, 2010, 03:03:14 pm by eightAs »
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Offline astarmathsandphysics

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Re: CIE P3 doubt ~
« Reply #1 on: January 01, 2010, 03:02:40 pm »
l'hospital's rule
when f=g=0, use f/g=f'/g'

Offline eightAs

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Re: CIE P3 doubt ~
« Reply #2 on: January 01, 2010, 03:04:12 pm »
l'hospital's rule
when f=g=0, use f/g=f'/g'
Do you have notes on l'hospital's rule.
« Last Edit: January 01, 2010, 03:06:34 pm by eightAs »
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Offline astarmathsandphysics

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Re: CIE P3 doubt ~
« Reply #3 on: January 01, 2010, 03:08:13 pm »
I will do a page on my website when I finish the big job on sunday

Offline eightAs

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Re: CIE P3 doubt ~
« Reply #4 on: January 01, 2010, 03:10:29 pm »
Is there a proof without assuming the fact that the derivative of e^x is e^x itself.
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Offline astarmathsandphysics

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Re: CIE P3 doubt ~
« Reply #5 on: January 01, 2010, 03:17:40 pm »
Yes using taylor series

Offline eightAs

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Re: CIE P3 doubt ~
« Reply #6 on: January 01, 2010, 03:23:45 pm »
Yes using taylor series
Can you post it when you're free please.
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Offline astarmathsandphysics

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Re: CIE P3 doubt ~
« Reply #7 on: January 01, 2010, 03:29:52 pm »
Will post a link when I do that page of notes

Offline astarmathsandphysics

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Offline eightAs

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Re: CIE P3 doubt ~
« Reply #9 on: January 12, 2010, 11:43:42 am »
Thank you very much.  :)
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Offline astarmathsandphysics

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Re: CIE P3 doubt ~
« Reply #10 on: January 12, 2010, 11:47:39 am »
No probs. Over the next few year I waim to write 8000 pages of maths notes.