Matrix Operations Quiz

Given matrices A = [[3, 4, 2], [1, 1, -3]] and B = [[1, 3, 7], [-4, -6, 2]], find the (2,1) entry of matrix C = 2A - 3B.

• -14

• 14

• 11

• 10

Given A = [[1, 1, -9], [3, 2, 1]] and B = [[-3, 1, 1], [-4, -6, 2]], find the (1,3) entry of C = 5A + 2B.

• -43

• 43

• 41

• -41

Solve for x in the matrix equation [[x, y, z], [-x, 1, 1]] = [[2, y, z], [-2, 1, 1]].

• x = 2

• x = -2

• x = 0

• x = 1

If A = [[4, 2], [2, 1]] and B = [[2, 8], [1, 5]], find the (1,1) entry of AB.

• 10

• 12

• 2

• 1

For matrices A = [[4, 2], [3, -2]] and B = [[2, 8], [1, 5]], find the element in the second row, first column of BA.

• 6

• 4

• 8

• 2

Given A = [[1, 1, 2, 7], [2, -3, 2, 1]] and B = [[2, -3], [1, 4], [-1, 0], [2, -1]]. What is the size of AB?

• 2x2

• 2x4

• 4x2

• The product AB is not defined.

Given A = [[1, 1], [2, 3]] and B = [[8, 1], [2, 7]]. What is the size of AB?

• 1x1

• 2x2

• 2x1

• The product is undefined

Find the matrix AB given A = [[2, 3], [-1, 1]] and B = [[3, -2], [1, 4]].

• [[9, 10], [-2, 6]]

• [[9, 6], [-2, 10]]

• [[10, 9], [6, -2]]

• [[6, 10], [9, -2]]

If A = [[3, -1, 2], [1, 4, 6]] and B = [[0, 4], [2, -1], [3, 0]], find the (2,1) element of AB.

• 22

• 20

• 21

• 23

Given A = [[3, -2, 1], [-1, 2, 3]] and B = [[1, 7], [-2, 1], [4, 3]], find the element in position (1,2) in the product AB.

• 11

• 21

• 7

• 17