Matrix multiplication

The product of matrix A and Identity matrix is

• Matrix A

• Identity matrix

• Null matrix

Product of matrix A and Null matrix is

• Null Matrix

• Matrix A

• Identity matrix

(A+B)C = AB + BC

• True

• False

(AB)C = (ABC)

• True

• False

For matrices A and B, will matrix multiplication be always commutative?

• Yes

• No

If matrix A is of order 2*3 and matrix B is of order 3*4, what is the order of AB?

• 2*4

• 3*2

• 3*3

• 2*3

Which of the following statements is TRUE about matrix multiplication?

• Matrix multiplication is always commutative

• Matrix multiplication is always associative

• Matrix multiplication is only defined for square matrices

• Matrix multiplication always results in a square matrix

Which of the following must be true for the product AB to be defined?

• The number of columns in A must equal the number of columns in B

• must be a square matrix

• The number of columns in A must equal the number of rows in B

• The number of rows in A must equal the number of rows in B

Let A be 3*4 matrix and B be 4*2 matrix. What is number of elements in resultant matrix AB ?

• 6

• 8

• 24

• 12