Graphing calculators such together the TI83 and also TI84 are able to do countless different operations through matrices, consisting of multiplication. Here, we will certainly go end the steps needed come multiply two matrices in this form of calculator utilizing the complying with example.

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Table the Contents

## Step-by-step through an example

Find the product the the matrices.

(AB=left<eginarrayccc-1 & 5 & -2\ 3 & 7 & 7\endarray ight>left<eginarraycc4 & 0\ 1 & 1\ 3 & 9endarray ight>)

### Step 1: go into the an initial matrix into the calculator

To get in a matrix, press <2ND> and (left).

(Note: part older models that the TI83 calculators have actually a procession button)

Use the ideal arrow key to walk to the modify menu.

Press enter to pick matrix A.

Type in the dimension of the matrix and also the worths by typing each number and also pressing . Note that the first matrix is a 2 x 3 matrix (rows through columns).

(A=left<eginarrayccc-1 & 5 & -2\ 3 & 7 & 7\endarray ight>)

### Step 2: enter the 2nd matrix into the calculator

Press <2ND> and also (left).

Press the right arrow crucial to walk to the modify menu.

Press <2> or highlight 2. and also press .

Type in the size of the matrix and also the values by inputting each number and also pressing . Note that the second matrix native our instance is a 3 x 2 matrix (rows through columns).

(left<eginarraycc4 & 0\ 1 & 1\ 3 & 9endarray ight>)

### Step 3: press <2ND> and also to quit out of the procession screen

This will take you to a blank screen. If girlfriend skip this step, your calculator might (depending on whereby your cursor is) try to placed matrix A within of procession B, causing an error.

### Step 4: choose matrix A and matrix B in the NAMES food selection to uncover the product

From the blank screen, press <2ND> and also (left) and also stay at the names menu.

Press to choose matrix .

To select matrix , go back into the matrix food selection by pressing <2ND> and (left).

Press <2> or highlight 2. and press .

Press to main point the matrices.

From here, you have actually your last answer. We can now write:

(eginalign abdominal &=left<eginarrayccc-1 & 5 & -2\ 3 & 7 & 7\endarray ight>left<eginarraycc4 & 0\ 1 & 1\ 3 & 9endarray ight>\ &=oxedleft<eginarraycc-5 & -13\ 40 & 70\endarray ight>endalign)

## Common error: DIM MISMATCH

Suppose the you go with these steps and also end up v the adhering to screen.

In this case, you should examine two things:

Did you go into the correct matrix information and also did you choose the exactly matrices to multiply?Is the product defined?

If you entered the matrices correctly, then this error means that the product is undefined. Specifics if you compose out the size of the matrices, the inside numbers should match. In the instance above, we had a 2 x 3 and also a 3 x 2. Notice that the number on the inside match, so the product was defined and also we to be able to uncover an answer.