HP 49g+ User Manual
Page 125
Page 9-8
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:
m
n
nm
n
n
m
m
a
a
a
a
a
a
a
a
a
A
×
=
L
M
O
M
M
L
L
2
1
2
22
21
1
12
11
,
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