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20-Turquoise
October 25, 2018
Solved

Plotting local max-min-points ?

  • October 25, 2018
  • 3 replies
  • 3115 views

  Hello Everyone.

  From :

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       Plotting local max-min-points ?

           Thanks in advance.

                 Regards.

Best answer by Werner_E

@lvl107 wrote:

Could you attach *.xmcd ? ( I'm afraid I may hit wrong key stroke... )

    Best Regards. 


Hmm, really!??

Here's a slightly different approach:

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Unfortunately the more direct and logical

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does not work in Mathcad - muPad is not capable to find the solutions.

3 replies

21-Topaz II
October 25, 2018

Hi,

 

Set a function that is the derivative of f(x).

Use the root function on this derivative within a range to determine unique roots.

 

You now have enough info to plot the points.

 

Capture.JPG

24-Ruby IV
October 25, 2018

May be like thif-x.png

lvl10720-TurquoiseAuthor
20-Turquoise
October 25, 2018

Many thanks both of you, Valery.Smiley HappySmiley HappySmiley Happy And I still have a query : "How to prove what point is local min-point ?

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Best Regards.

25-Diamond I
October 25, 2018

 

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25-Diamond I
October 25, 2018

In case of this function Mathcads symbolics is capable enough to give you al solutions, so you should use it.

If your goal is to limit the results to x1<x<x2 you may use the "assume" modifier.

B.PNG