[Solved] Math Help

[dantay9]

I am making a trinomial solver because I hate having to solve them and not knowing if they are even solvable. I have the equation split up and the necessary parts assigned to variables, but I don't know where to go from here. Can someone point me in the right direction. Thanks in advance.

Edited March 12, 2009 by dantay9

[qazwsx]

I think most solvers use matrices to solve equations.

[dantay9]

I know that solving systems of equations is easiest using matricies, but can you solve just one equation using matricies?

Edited March 12, 2009 by dantay9

[martin]

I know that solving systems of equations is easiest using matricies, but can you solve just one equation using matricies?

Assuming you have got the factors worked out correctly then I assume that for each factor the sign could be +ve or -ve, and for each pair of factors for the square term any of the other factors for the linear term might be the correct ones. So you can go through all possibilities.

Lets say the sign for the first square term factor is $a; the sign for the second square term factor is $b; the sign for the first linear term factor is $c and the second is $d.

Then we can do this

For $as = -1 To 1 Step 2;for either sign of the first square factor
     For $bs = -1 To 1 Step 2;etc
         For $cs = -1 To 1 Step 2
             For $ds = -1 To 1 Step 2
                 For $j = 0 To UBound($SquaredFactors) - 1
                     For $k = 0 To UBound($ConstantFactors) - 1
                         If ($as * $SquaredFactors[$j][0] + $cs * $ConstantFactors[$k[0]) * ($bs * $SquaredFactors[$j][1] + $ds * $ConstantFactors[$k[1]) = 0 Then
                           ;we have found an answer
                         EndIf
                       ;try with factors swapped
                         If ($as * $SquaredFactors[$j][0] + $cs * $ConstantFactors[$k[1]) * ($bs * $SquaredFactors[$j][1] + $ds * $ConstantFactors[$k[0]) = 0 Then
                            ;we have found an answer
                          EndIf
 
                     Next
                 Next
             Next
         Next
     Next
 Next

But this seems like a very complicated way to solve the problem and it's restricted to integer results, although I think your functions could be simplified. Why not use a more conventional approach?

EDIT: By conventional I mean

ANS = (-b +/-(b² - $ac)^1/2)/2a

Edited March 12, 2009 by martin

[dantay9]

I decided to use this way because my plan was to factor the trinomial, not solve it. I don't want an exact answer. I want to know if it can be factored.

[martin]

I decided to use this way because my plan was to factor the trinomial, not solve it. I don't want an exact answer. I want to know if it can be factored.

OK, you can do it any way you want of course.

Anyway, was my suggestion any help?

[dantay9]

Oh! I forgot to reply back. Yes, it was a lot of help. It worked great.