Matrix Basics

Question 1

Order of row and column

Answer 1

(Row,Column)

Question 2

Matrix Addition and Subtraction Rules

Answer 2

Must be the same size

Question 3

What is an array?

Answer 3

A collection of elements within a single variable.

Question 4

1D Array

Answer 4

Single row or column vector

Question 5

2d Array

Answer 5

has both rows and columns

Question 6

3d Array

Answer 6

Rows, columns and layers

Question 7

Row vector

Answer 7

horizontal single line array

Question 8

Column vector

Answer 8

vertical single line array

Question 9

Matrix Addition and Subtraction

Answer 9

matrices must be same size
calculation is done element by element

Question 10

Requirement for matrix multiplication

Answer 10

Inner dimensions must be the same

Question 11

What does inner dimensions must be the same mean?

Answer 11

Rows must match columns i.e. 1x3 * 3x1

Question 12

Matrix Arithmetic: Cumulative Law of Addition

Answer 12

A+B = B+ A

Question 13

Matrix Arithmetic: Associative Law of Addition

Answer 13

A+(B+C) = (A+B)+C

Question 14

Matrix Arithmetic: Associative Law of Multiplication

Answer 14

A(BC) = (AB)C

Question 15

Matrix Arithmetic: Distributive Laws

Answer 15

A(B+C) = AB + AC
(A_B)C= AC + BC

Question 16

Things to remember about Matrix division

Answer 16

-Typically not considered a matrix operation
-Inverted Matrices are used e.g. Ax=b = x = a ^-1b
-Not all matrices can be inverted
-Typically we use element by element in matlab