Trying to get the inverse of a matrix

Create a square matrix at mots 3X3. Then you can multiply it by a scalar, or scare it, or calculate its determinant, and inverse. With two matrices that have the same dimensions you can perform .additions/subtractions or multiplications.

What do you mean by "solve matrix"? Do you want its determinant? Its inverse? The eigenvalues and eigenvector? Solve a system of linear equations?

Let your system of linear equations be [A][X]=[B] where [A] is a 3x3 matrix, [X] is column vector ( a 3x1 matrix) , and [B] is also a column vector or (3x1) matrix.

Assuming you are able to invert the [A] matrix to find [A^-1].
Multiplying on the keft by [A^-1] the system of equations you get
[A^-1].[A][X]=[A^-1][B].
But since the product [A^-1][A] is the (3x3) Identity matrix, the left side of the equation is jut [X], while the right side is [A^-1][B]. As you can see it is not [B][A^-1] .
To solve your problem, you should define your [A] matrix, define the [B] column vector (3x1) matrix, then perform the operation [A^-1][B] using the [X to -1] power key to calculate the inverse [A^-1].

A singular matrix has no inverse. It's the equivalent of zero: trying to take the inverse of zero is an error. Check the matrix to make sure you have entered it correctly. If the error persists, could you post the matrix in question?

What do you mean by "solve a matrix"? Find the inverse? Find the determinant? Find the solution to a system of linear equations? Within limits the fx-115ES can do any of these and more.

The procedures are described in the "Matrix Calculations" section of the manual. If you still have problems, please reply to this post specifying what you want to do.

Create the Matrix in the Run/Mat screen


Press 1 to enter Run/Matrix screen


Press F1 >MAT. The next screen opens. Enter the dimensions (3x3)


In the template enter the coefficients. Press EXE after each item.


Press the AC button to exit thye matrix editor screen.

Press SHIFT 2 to type the Mat identifier on the command line.
Press the ALPHA key followed by A (if you are working with the A matrix.)
At this point you have Mat A on the command line.
Press SHIFT ) to get the x^-1 function. That is the one that calculates the inverse of a Matrix.

1. Press [2nd] [X to -1] under [MATH[ to access the (Matrix) menus.
2. Use right arrow to highlight [EDIT]
3. Press [1:A] to edit (create from scratch) the A matrix.
4. On the line MATRIX[A] line cursor blinks on 1
5. Enter m dimension (3) and press [ENTER].
6. Cursor moves to the second dimension (n). type 3.
7. Press [ENTER].
8. A 3x3 matrix template is displayed with A_11 element highlighted.
9. Replace the value 0 with your value for A_11.
10. Press [ENTER].
11. Type a value and press [ENTER].
12. When finished, press [2nd][QUIT] to exit the matrix editor.
    

Your matrix is ready to be operated on (squaring, multiplication by a scalar, inverse if matrix is non-singular, determinant.) All operations are available under [2nd][X^-1](Matrix) [=>][MATH].

Hello,
Here is the solution for th FX-991ES.
Hello,

The error may be due to the key you used to signifie inverse. It says in the manual that you should use the key x^-1 not the one used to input general powers.
Here is screen capture from the Appendix to the manual. The picture shows the sequence of keys to press to obtain the inverse of a 2x2 matrix. It is taken from page 41 of Appendix


The matrix used in the exemple is
a_11=2 a_12=1 a_21=1 a_22=2
Here is the link to download the manual and the appendix

http://support.casio.com/manualfile.php?rgn=1&cid=004001004
The link is for FX991ES. Look there foe you manual.

Hope it helps

Hello,
The so-called (2x1) matrix is not a matrix. It is a vector.
Hope it helps.

Hello,
You cannot calculate the inverse of an arbitrary matrix. It must be a square matrix (nxn) with non zero determinant. Make sure dimensions m and n are equal. (2x2), (3x3)

To calculate its determinant [Shift][MATRIX] [7:det] [SHIFT][MATRIX][3:MatA] close the right parenthesis and [=].
If determinant is different from zero then you can calculate its inverse.
If matrix MatA has already been defined, you calculate its inverse as follows;
[SHIFT][MATRIX][3:MatA] [X^-1][=]. Use the X to -1 power , the one under [MODE].
For well-behaved matrices you calculate the inverse directly without worrying about the determinant.
Hope it helps.