Test Review for Matrix

What must be true in order to ADD two matrices?

• They must be square.

• The dimensions must be equal.

• The determinant can't equal 0.

• The column of the 1st must equal the row of the 2nd.

If the matrices can be multiplied, what dimension is the product? If not, write undefined.

• undefined

• ( 3 x 1 )

• ( 1 x 2 )

• ( 3 x 2 )

Which of the following must be true for a matrix to be invertible? Choose all that apply.

• The matrix must be square.

• The determinant must be zero.

• The determinant must not be zero.

• The matrix cannot have any negative entries.

Evaluate the determinant of the matrix.

• -21

• 0

• 9

• 12

find: B*A

• 47     30
  9     5

• 17     15
  42     35

• 10     25
  7     1

• not possible because rows do not match columns

Which element is located in A₂₃?

• -3

• 5

• -9

• 2

What is a Matrix?

• An equation of over 5 numbers or symbols 

• A set of numbers in rows and columns

• A method of finding the n^th value of a series

• A complicated number system

Evaluate the value of det (G).

• 8

• -8

• 18

• -18

What is a Matrix?

• An equation of over 5 numbers or symbols 

• A set of numbers in rows and columns

• A method of finding the n^th value of a series

• A complicated number system

How many rows are in a 7 x 3 matrix?

• 7

• 3

• 21

• 10