Dawnbridge

TI-84 Plus CE field manual for IB Math

AI HL only · 34 of 41

34

Matrix arithmetic

AI HL

Store two matrices and evaluate a matrix expression such as A3B on the calculation screen.

Goal

Given A=[1321] and B=[2103], find A3B.

1

Press to open MATRIX, move to EDIT, choose 1:[A], set the dimensions to 2 x 2, and fill the rows 1, 2 and 3, 1, pressing after each entry.

NORMALFLOATAUTOREALRADIANMP
MATRIX[A] 2 x2
1231
2

Go back to MATRIXEDIT, choose 2:[B], and enter the second matrix the same way.

NORMALFLOATAUTOREALRADIANMP
MATRIX[B] 2 x2
2013
3

Return to the home screen with . Open the matrix menu with and press to paste [A]. Press for the cube, press to leave the exponent, paste [B] the same way ( ), and press .

NORMALFLOATAUTOREALRADIANMP
[A]3[B]
[56735457]
Result

A3B=[56735457].

Your turn

Work each one on your calculator, then check the answer.

  1. 1

    Given A=[2111] and B=[1230], find A3B.

  2. 2

    Given A=[12−10] and B=[3012], find A3B.

  3. 3

    Given A=[0121] and B=[2310], find A3B.