Bug in command "Factors"

Robert T. shared this problem 1 year ago
Solved

While programming an applet for polynomial functions and comparing factors and multiplicites I stumbled over a strange behaviour of the Factors command in Geogebra classic 5. It can simply be reproduced:


Type the following commands:

f(x)=x^2-1

a=Factors(f)

Result is correct: a is shown as { {x-1,1}, {x+1,1} }


Now change f(x) to f(x)=0 by typing f(x)=0.

Result is confusing: a is now shown as { {x-1,1}, {x+1,1}, {0,1} }


Type f(x)=0 again:

Result is growing: a is now shown as { {x-1,1}, {x+1,1}, {0,1}, {0,1} }


The factors list can be resetted by using any other definition of f(x) unequal to zero. That's my suggestion for a work-around.


A little confusing is the result for f(x) = 1:

The factors list is shown as {{0,0}} which of course is unique and can be interpreted as 1, but I have a doubt that it's intuitive for pupils.

Comments (3)

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1

Thanks, we'll check!

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1

Fixed for next release (v504)

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1

Looks good! Thank you!

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