Unit 1 MATRICES

Dr. ShildneckFall, 2015

WHAT IS A MATRIX?•A Matrix is a rectangular array of numbers placed inside brackets.

•The plural form is “MATRICES.”

The DIMENSIONSof a Matrix indicate its size.

• The DIMENSIONS are determined by the number of rows and columns in the array.

•Rows are lists of numbers across the array.

•Columns are lists down the array.

DIMENSIONS

[ 𝟏 𝟓 −𝟏𝟏𝟐 𝟎 𝟕 ]

Determine the dimensions of the matrix.

Equal MatricesFor two matrices to be equal,

1. They have to be the same size.

2. Each entry (in corresponding positions) must be equal.

Equal MatricesDetermine the values of the unknowns that make the two matrices equal.

[𝟏 𝟓 −𝟏𝒂 𝟎 𝟕 ]=[ 𝟏 𝟓 𝒃

𝟏𝟐 𝟎 𝟕]

Special MatricesNumber Matrix (1x1)Row Matrix (1xN)Column Matrix (Nx1)Square Matrix (NxN)Zero Matrix: All entries are zero

Notations with MatricesA matrix can be given a “Name.”Typically use a capital letter.

The entries in a named matrix also have names given by the same lowercase letter and a subscript that refers to its position (row, column)

Notations with MatricesGiven the matrix find each of the following.

A =

1) a11 2) a32 3) a23

Tables and MatricesA matrix can also be though of as a table of data. Matrices are often created from data so that the information can be utilized more efficiently by computers and analysts.

Tables and MatricesCreate an appropriate matrix for the data provided.

Laps Run Practice Day

STUDENT

Monday Tuesday Wednesday

Billy 5 8 9

Nancy 7 8 9

Sam 5 10 12

ASSIGNMENTAssignment #3

WSIntroduction to Matrices