1 ACCEPTED SOLUTION
Accepted Solutions
No need to calculate the reduced row echolon form manually, you may use rref.
But as rank(M)=rank(ME)=2<3 we already know, that we have an infinite number of solutions. You may google "Rouché-Capelli theorem".
Strange enough symbolic evaluation will yield wrong result!!?? Probably the result of numerical inaccuracy due to the awful automatic switch to float mode.
Looks like there is a bug in your version (14, if I remember correct).
This is what Mathcad 15 M020 comes up with:
I have only Mathcad 14. By the way, and could you do me a favor, give a sreenshot of :
in Mathcad 15 M020. Thanks.
I get the same (wrong) result as you. Thats what happens quite often with numeric methods. The symbolics would refuse to evaluate that expression (with an inappropriate error messoge, though).
But why would you use lsolve on a system of equations which clearly has no solution (different rank for coefficient matrix and augmented matrix)?
Again you would see numeric inaccuracy if you evaluate the determinant numerically.
BTW, you could install the 30 day eval of Mathcad 15 on a spare computer, if you have that oportunity or in a VM, or use Mathcad Prime2 Express parallel with your MC14. Express won't let you do symbolic operation and solve blocks after its 30 day trial period. Numeric evals should work.
