Formula book: quadratic equation formula has stopped working.

[Former user]

The formula for the quadratic equation has stopped working and it is a critical fault as our students must use it in this mathematics course constantly. This bug makes fast calculating much more difficult as now every exercise has to be partially solved without calculators.

[gilga]

I’ve typed this:

a=6

b=11

c=−35

Then I choose and click in the list of formula, the quadratic formula:

x1 = (-b + sqrt(b^2 - 4*a*c))/(2*a)

And it displays the result:

= 1.66666666666666666667

So, it’s working for me.

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[Helder Correia]

It’s working fine. BTW, you can be more productive by defining these user functions:

quadx1(a;b;c) = (-b + sqrt(b^2 - 4*a*c))/(2*a)
quadx2(a;b;c) = (-b − sqrt(b^2 - 4*a*c))/(2*a)

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