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#1 2013-12-07 16:45:10

MathsIsFun
Administrator
Registered: 2005-01-21
Posts: 7,534

Finding Maxima and Minima using Derivatives

New Page: Finding Maxima and Minima using Derivatives

Please let me know what you think, anything I may have got wrong, suggestions, etc,


"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

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#2 2013-12-07 20:58:02

bob bundy
Moderator
Registered: 2010-06-20
Posts: 6,259

Re: Finding Maxima and Minima using Derivatives

hi MathsIsFun,

Good page, thanks.  smile

When I was at school, my teacher wrongly called a saddle point,  a 'point of inflexion' and I think this confusion is widespread.  Would you be able to add a footnote about inflexion (or inflection if you prefer) to clarify ? 

http://en.wikipedia.org/wiki/Point_of_inflexion

Bob


You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#3 2013-12-07 21:13:08

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 82,779

Re: Finding Maxima and Minima using Derivatives

Hi MIF;

Good page. Please expand on the inflection points if you have the time.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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#4 2013-12-07 23:06:43

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,860

Re: Finding Maxima and Minima using Derivatives

Hi MIF

Nice page.

You can maybe add that the better way of finding out if an extremum is a maximum or a minimum is looking at the sign changes at the zeros of the first derivative. It works for any function continuous between the two zeros.


“Here lies the reader who will never open this book. He is forever dead.

“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

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#5 2013-12-08 15:16:29

MathsIsFun
Administrator
Registered: 2005-01-21
Posts: 7,534

Re: Finding Maxima and Minima using Derivatives

Thanks Guys! Good suggestions all.


"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

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#6 2013-12-10 11:59:18

Brainwave
Member
Registered: 2013-12-10
Posts: 2

Re: Finding Maxima and Minima using Derivatives

Bobbym I love your words " if you cannot overcome with talent, overcome with efforts."


"MATHEMATICS", the birth place of great THINKERS.

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#7 2013-12-19 12:06:21

MathsIsFun
Administrator
Registered: 2005-01-21
Posts: 7,534

Re: Finding Maxima and Minima using Derivatives

Wrote a page on Inflection Points ... created new topic for you guys to comment on: http://www.mathisfunforum.com/viewtopic.php?id=20306


"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

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