Sometimes maxima of a function are wrong

WolfgangSchill shared this question 9 years ago
Answered

Hello,

Sometimes maxima of a function

f(x)=e^(-x^2)*cos(k x)

are wrong

Please see:

http://www.geogebratube.org...


Wolfgang

Comments (6)

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1

hello

Max[ Function, left-x, right-x ]

Calculates the maximum point for function in the given interval. Function should only have one maximum point in the interval.

(i do not know english but i think one instead on is correct)

from help

http://wiki.geogebra.org/en...


saludos

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TNX,

now I tried Extremum:

Extremum[Function f,left-x,right-x]

Finds the extremum of f in the open interval <left-x,right-x>. Function f should be continuous in [left-x,right-x], otherwise false extremums near discontinuity might be calculated.


https://ggbm.at/549937

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Hi Wolfgang,


I tried the "View in browser: Version 4.0" link in your post and didn't spot any missing extrema. For which values of k and x should I look for missing extrema?


Cheers,

Zbynek

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Strange!


My local Webstart-Geogebra has missings extremas. But if I click on the the attachment of my last message there are no missing extremas.


87258b8e7406448639f1824c1e6690d9

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Hi Wolfgang,


in that case please check that you are using version 3.9.294.0r (Help > About).


Cheers,

Zbynek

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I am working with Geogebra 3.9.294.0r Webstart on DEBIAN Squeeze and GNOME-Desktop.


It was not possible to open the saved geogebra file in a second window. Only the focus changed to the old window.


After closing the window and reopening the geogebra file all extremas are found.


Greetings

Wolfgang

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