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This system of linear equations can be written as a matrix equation, A
n
×
m
⋅
x
m
×
1
= b
n
×
1
, if we define the following matrix and vectors:
mn
nmnn
m
m
aaa
aaa
aaa
A
×
=
L
MOMM
L
L
21
22221
11211
,
1
2
1
×
=
m
m
x
x
x
x
M
,
1
2
1
×
=
n
n
b
b
b
b
M
Using the numerical solver for linear systems
There are many ways to solve a system of linear equations with the calculator.
One possibility is through the numerical solver
‚Ï
. From the numerical
solver screen, shown below (left), select the option 4. Solve lin sys.., and
press @@@OK@@@. The following input form will be provide (right):
To solve the linear system A⋅x = b, enter the matrix A, in the format [[ a
11
,
a
12,
… ], … [….]] in the A: field. Also, enter the vector b in the B: field.
When the X: field is highlighted, press @SOLVE. If a solution is available, the
solution vector x will be shown in the X: field. The solution is also copied to
stack level 1. Some examples follow.
The system of linear equations
2x
1
+ 3x
2
–5x
3
= 13,
x
1
– 3x
2
+ 8x
3
= -13,
2x
1
– 2x
2
+ 4x
3
= -6,
can be written as the matrix equation A⋅x = b , if