Matrices Introduction

Multiply

• 20     15    -10
  30     -5         0

• -20      15     -10
  30     -5          0

• 1        8       3
  11     4        5

• 20     -15     10
  -30         5        0  

What is the third element of the first column?

• 1

• -x

• 100

• 3

How many rows does the above matrix have?

• 1

• 3

What is the second element of the second column?

• -10

• 8

• 25

• 3

How many rows does the above matrix have?

• 1

• 3

The matrix above is named A. AB is possible only if B has

• 1 row

• 1 column 

• 3 rows

• 3 columns

The order of the above matrix is

The matrix above can only be added to another matrix which has

• 2 elements

• 2 columns

The sum of the two matrices above is equal to

• The inverse matrix

• The identity matrix

• The diagonal matrix

• The unit matrix

The order of the above matrix is