Error in Geogebra when displaying numbers

BSS_Math shared this question 2 months ago
Answered

Hi,

I recently made this program https://www.geogebra.org/m/xMq2XJkB and I have noticed that when Geogebra is calculating rationals, specifically 1/2, the program throws out awkward numbers when using the expand command on a factored expression. However other rational numbers display properly.

Is this a bug in the program?

Comments (7)

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try

g(x) = Polynomial(f)

see also: "note" in https://wiki.geogebra.org/e...

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sorry, above wrong.

workaround: use CAS

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This seems to have worked. I haven't done any work in Geogebra using CAS. This error seems to be a bug. Hopefully it gets resolved in the next stable release.

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o define f(x) = Numerator(a) / Denominator(a) (x - r) (x - s) instead f(x) = a (x - r) (x - s)

para evitar el almacenamiento flotante

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This partially corrected the problem however when setting one of the roots to a rational number, the same error persisted on the b and c values of the standard form of the polynomial.

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Looks like a small bug - we'll check!


I think you can work around it - try changing Options -> Rounding


https://www.geogebra.org/cl...

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Thanks. The CAS option provided was a workaround but this seems to be a bug. I tried mathmagics method but this only worked when the factors were integers. Once they became rational, I got similar large numbers for the numerator or denominator of the rational numbers.

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