# CAS problems - solve doesn't work

Stefan shared this question 3 years ago

Hi,

I try to use CAS to find a solution for my math homework.

The function is P(x)=x^4+x^3+ax^2+bx+c

I should find the values for a,b and c so that factors (x+2),(x+3) and (x-1) are true.

Alas, I put this into CAS and CAS returns a solution of {} which apparently is its way to say there is none. I follow a step for step solution for this assignment with screenshots that show what one should type into CAS; there it is clearly visible that CAS should output {{a=-11,b=-9,c=18}} instead of {}.

Am I doing something wrong, or is this a bug in my CAS version?

I use version 6.0.542.0-win (07 June 2019). This is the first installation of Geogebra on this machine.

2

Try a*x^2 instead of ax^2 (or try the new CAS Calculator app http://www.geogebra.org/cas )

1

thank you that helped a lot, and I guess it is also the source of some other problems I have not yet written here.

I would use a stand alone CAS but when the exam comes there will only be geogebra classic on the PC, so I need to accustom myself as much as possible to that.

Do I need to mark this thread as solved somewhere?