Matrices

To add or subtract matrices, which of the following must be true?

• They are the same matrix

• They have the same dimensions

• Rows in the 1st matrix must have the same # of terms as the columns as the 2nd matrix

• All matrices can be added

Tags

CCSS.HSN.VM.C.8

Find 2A-3B

• -3 1

  7 -1

• 1 0

  1 -4

• -4 0

  6 -1

• -14 -5

  11 -3

Tags

CCSS.HSN.VM.C.7

CCSS.HSN.VM.C.8

These matrices are being multiplied. Determine the dimension/size of the new matrix. 

• Can't multiply them
• 4  x  2
• 3  x  3
• 4  x  3

Given matrices A & B: 
A is a (4x33) matrix
B is a (33x1) matrix
 What are the dimensions of the product of A times B?

• 4x1
• 4x33
• 33x1
• Matrix does not exist

find: B*A. Remember, ORDER MATTERS!

• 47 30

  9 5

• 17 15

  42 35

• 10 25

  7 1

• not possible because rows do not match columns

Find the product of the matrices.

• A
• B
• C
• D

Evaluate the determinant of the matrix BY HAND.

• -21

• 0

• 9

• 12

Find the determinant of the matrix BY HAND.

• A

• B

• C

• D

Calculate the determinant. You will need a calculator.

• 0

• -15

• -70

• 10

Determine if the matrix has an inverse, if so find it. It is to your advantage to know how to do this by hand AND by calculator.

• No

• 0 1

  -1 2

• -1 3

  1 -2

• 2 -1

  -1 1