Maple Tutor
Part 10: Row operations
on matrices
- Unassign your variables again,
and ask Maple to solve
| x + 4y + 3z = 10 |
| 2x + y - z = -1 |
| 3x - y - 4z = 11 |
- What happens in Step 1? What
do you think it means? To check this out, we need Maple's linear algebra
package; enter
with(linalg);
This will load a wide range of useful-looking commands. The first one
we need is matrix -- enter the augmented matrix for our current problem as
A:=matrix(3,4,[1,4,3,10,2,1,-1,-1,3,-1,-4,11]);
This tells Maple to construct a matrix and fill its entries from
the following vector of numbers, reading across the first row, then the second,
then the third.
- First let's see how to row reduce
a step at a time. Then we will see that a single command will do the whole
job. Try the following sequence of commands:
addrow(A,1,2,-2);
addrow(%,1,3,-3);
mulrow(%,2,-1/7);
Got the idea? Finish the row reduction, or at least take it far
enough to decide what went wrong when you asked Maple to solve the
system of equations. (The third type of row operation is called swaprow in
Maple. You may not need it for this problem.)
- Finally, let's go directly to
the reduced row echelon form of in one step:
rref(A);
This should show you in another way that our linear system is inconsistent.
