Solving Systems of Equations

[sahand]

Hi,

I have the following worksheet and I am trying to solve for C1 and C2. The error that I am getting says that "Somethings is wrong with the solve block..."

The subscripts for C were entered as C[1 and C[2.

Any help would be appreciated.

Thanks!

[RichardJ · Accepted solution]

Numerous issues.

[sahand]

Thank you so MUCH! I truly appreciate your help

[sahand]

Hi Richard,

So i tried expanding the equation to solve for 3 variables instead of 2 and I am getting an error sying that the matrix I am trying to solve for is undefined!

Is there something wrong with 'd4' and 'EQ4(C)' ?

Thanks in advance!

[Fred_Kohlhepp]

sahand noorizadeh wrote:

Is there something wrong with 'd4' and 'EQ4(C)' ?

Thanks in advance!

Yes! The symbolic processor knows what the dirac delta function is (D(C1-C2+C3)), but the numeric processor doesn't have a clue. Putting in an approximate definition for that function repairs the problem.

[RichardJ]

Interesting approach. I think I would prefer to just remove that term from the expression and accept that the solution is then not valid for C3=C2-C1 (because when C3 is not equal to C2-C1 the Dirac delta function is zero). That is more exactly correct, I admit that it does require manual manipulation of the expression, whereas your approach does not.

Incidentally, if you move the Dirac delta defintion above the defintion of EQ4 then none of the chnages you made to the solve block are necessary.