Introduction to Matrices

Intro To Matrices
Fill out the notes using this lesson. Don't just copy it. Pay attention to the process of each operation. I want to see done notes on Monday.

What is a Matrix?

​A rectangular array of variables or constants in rows or columns, usually enclosed in brackets.

"Columns hold things up" (up and down). Rows are left to right.

What are the Elements?

​Individual

Values

​x

​row

y

column

​-2

​5

​40

​52

​21

​32

• Note: Matrices are names using a Capital Letter. Make sure you pay attention to how we found the answers for 1-6.

Dimensions

​A matrix with m-rows and n-columns is
said to be an "mxn" matrix.

​1x3

​4x2

​3x4

​2x6

• You say this "one by three" or "four by two"

Equal Matrices

​Two matrices in which each element in one matrix
is equal to the corresponding element in the other matrix.

Special Matrices

​[a b c]

Addition and Subtraction

• Matrices have to be the same size.

• Add or subtract numbers that are in the same spot.

​Not Possible; Not
the same size.

Scalar Multiplication

• #15: multiply each number in the matrix by 3. Dimensions will be the same size.

• #17: Do scalar multiplication first and then add resulting matrices if possible.

• #19: Add Matrices first and then do Scalar Multiplication.

Mrs. Christopher has your assignment. At least try to start it, but I won't be mad if you don't get it done.