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#1 2013-12-08 15:45:10

MathsIsFun

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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

#2 2013-12-08 19:58:02

bob bundy
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Re: Finding Maxima and Minima using Derivatives

hi MathsIsFun,

Good page, thanks.

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

#3 2013-12-08 20:13:08

bobbym

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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.

#4 2013-12-08 22:06:43

anonimnystefy
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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.

The limit operator is just an excuse for doing something you know you can't.
“It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman
“Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment

#5 2013-12-09 14:16:29

MathsIsFun

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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

#6 2013-12-11 10:59:18

Brainwave
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Re: Finding Maxima and Minima using Derivatives

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

#7 2013-12-20 11:06:21

MathsIsFun

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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