Issues with algebraic derivative in Cas mode

Drewan shared this question 3 months ago
Answered

Hi

I am a teacher in sixth form whose students sometimes use tools in Geogebra which I have not yet tried. In a test one Swedish student tried to use the f prime function in Cas mode as attachement shows. As the function was complex * this was a good idea. However the tool gave a faulty answer. I would like a comment from you. Is it correctly inserted or not. When using the same function in the normal graph mode I had no problems whatsoever to get the right answer so it seems to me there is a problem with the programming of CAS

*The function is both an product and a function composition so I cannot see that the attachment is correct.

Comments (6)

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Please post your file

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The syntax in the old CAS is f:= not f=


Try in the new version https://www.geogebra.org/cas

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The student did not type f =. This was my attempt to see if it made any difference.

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I should also want to say that the app was brand new, loaded the same day: Geogebra Classic. If there is a new version as Michael indicates it seems a shame that this was not included in the version that my students downloaded. I have indeed tried his link and there it functions but that leaves me in a predicament. Should I say that the students error was because of a faulty program version then that leaves in a positiona where I have to grant points for an error!

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The old one isn't faulty, you just have to use := to define functions

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