This system of linear equations can be written as a matrix equation, Anmxm1 = bn1, if we define the following matrix and vectors:

 

a

a

 

11

12

A =

a21

a22

M

 

 

M

 

an1

an2

L a1m L a

2m

O M

L anm nm

 

 

x

 

 

1

,

x =

x2

 

 

 

 

M

 

 

xm

 

 

 

m 1

 

b

 

1

,

b = b2

 

 

M

 

bn

 

 

n 1

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 Ax = b, enter the matrix A, in the format [[ a11,

a12, … ], … [….]] 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

2x1 + 3x2 –5x3= 13,

x1 – 3x2 + 8x3 = -13, 2x1 – 2x2 + 4x3 = -6,

can be written as the matrix equation Ax = b, if

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