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'Matrix calculator' data sets are designed to handle matrix
computations.
Up to five Matrices are defined in the Matrix Editor tab.
(Described below). Once defined, you type matrix expressions to be
evaluated in the Program tab, using variables to represent the matrices. A full
range of matrix operations are supported, and results appear on the text view.
 Program tab 
Type matrix expressions and other commands in the 'Program
tab'. You can even program loops for generating matrix series.
This example is a program included with Maths Helper Plus. It
solves simultaneous linear equations in any number of unknowns. You use the
'Matrix Editor' tab to input the equation coefficients in matrix 'A', and the
right side values as a column matrix 'B'. Click the 'Run' button to view the
solutions on the text view.
For example, consider these linear equations:
2x + 3y
– z = –7
–4y
+ 6z = 26
5x + 9y
+ 2z = –7
Then the coefficient matrix, 'A' is:
2 3 1
0 4 6
5 9 2
and the column matrix 'B' of right side values is:
7
The solutions appear on the text view like this:
Output
Solve the linear equations
with coefficients:
A = 2 3 1
0 4 6
5 9 2
and right side values:
B = 7
26
7
Then the solutions:
x
y
z
are as follows:
X = 1
2
3
 Matrix Editor 
This options tab has a large edit box where you enter and edit
matrices.
Type the elements of your matrix with commas between them,
like this:
1,
2, 3
4, 5, 6
7, 8, 9
Use expressions for the
elements, like this:
2/3,
3/4, 5/8
pi/4, pi/3, pi/7
sin25º, cos25º, tan25º
To enter large matrices
quickly, take advantage of the following short
cuts:

A blank line is filled with zero elements.

A comma with nothing to the left of it is the same as
zero.

Unfinished lines are finished off with zero elements if
there is another line with more elements. The longest line entered
determines how many zeros are required.
For example, enter
this:
1,2
<blank line>
,,,,,3,,4

to get this:
1,
2, 0, 0, 0, 0, 0, 0
0, 0, 0, 0, 0, 0, 0, 0
0, 0, 0, 0, 0, 3, 0, 4

 2 by 2 Matrix Calculations 
This tab has options to create working steps for basic matrix operations on
matrices 'A' and 'B'. The options are only available for 2 by 2 matrices.
Here is a sample output created by this option:
Calculations for 2×2
matrices
Matrix A = [ a11 a12 ]
[ a21 a22 ]
= [ 1 2 ]
[ 3 4 ]
The DETERMINANT of A is given by:
Det = a11×a22  a12×a21
= 1 × 4  2 × 3
= 2
The INVERSE of A is given by:
invA = [ a22/Det a12/Det ]
[ a21/Det
a11/Det ]
= [
2 1 ]
[ 1.5 0.5 ]
Matrix B = [ b11 b12 ]
[ b21 b22 ]
= [ 5 6 ]
[ 7 8 ]
Matrix Addition:
A + B = [ (a11+b11) (a12+b12) ] = [ p q ]
[ (a21+b21)
(a22+b22) ] [ r s ]
then: p = 1 + 5
= 6
q = 2 + 6
= 8
r = 3 + 7
= 10
s = 4 + 8
= 12
so A + B = [ 6 8 ]
[ 10 12 ]
Matrix Multiplication:
A × B = [ (a11×b11)+(a12×b21) (a11×b12)+(a12×b22) ]
[
(a21×b11)+(a22×b21) (a21×b12)+(a22×b22) ]
= [ p q ]
[ r s ]
then: p = (1×5)+(2×7)
= 19
q = (1×6)+(2×8)
= 22
r = (3×5)+(4×7)
= 43
s = (3×6)+(4×8)
= 50
so A × B = [ 19 22 ]
[ 43 50 ] 
