10 Questions

Questions and Answers

- 1.Farmer A had 4 ducks, 3 chickens and 2 cows while Farmer B had 9 cows, 4 pigs and 7 chickens. A matrix can be formed to represent the above data. Which one of the following would be a possible order of the matrix?
- A.
2 x 1

- B.
2 x 2

- C.
2 x 3

- D.
2 x 4

- 2.Which of the following is impossible?
- A.
Scalar Multiplication

- B.
Matrix Multiplication

- C.
Scalar Division

- D.
Matrix Division

- 3.What is an identity matrix and why is it called an identity matrix?
- A.
An identity matrix is a matrix with all diagonal entries as 1 and all non-diagonal entries as 0. It is called an identity matrix as it would give a null matrix as a result when multiplied by other matrix.

- B.
An identity matrix is a matrix with all diagonal entries as 1 and all non-diagonal entries as 0. It is called an identity matrix as it would not change the original matrix when multiplied by it.

- C.
An identity matrix is a matrix with all its entries as 0. It is called an identity matrix as it would give a null matrix as a result when multiplied by any other matrix.

- D.
An identity matrix is a matrix with all its entries as 0. It is called an identity matrix as it would not change the original matrix when multiplied by it.

- 4.(9 0 1 3 4) (0 7 3 0)A = (5 7 8 2 4) (1 3 6 2) (3 4 2 7 0) B = (7 8 9 2) (7 4 3 8) (8 3 2 5)Which of the following is possible?
- A.
A + B

- B.
A - B

- C.
A x B

- D.
A / B

- 5.Which of the following matrix operations is commutative?
- A.
Addition of Matrices

- B.
Subtraction of Matrices

- C.
Multiplication of Matrices

- D.
Division of Matrices

- 6.Which of the following is not a square matrix?
- A.
(1)

- B.
(5 8) (9 2)

- C.
(4 9) (16 25) (36 49)

- D.
(2 8 7 6 9) (8 7 6 0 3) (7 6 8 3 4) (1 4 7 2 6) (7 8 2 3 0)

- 7.(8 3 1 2) (7 8 2 5)A = (9 3 4 8) B = (4 8 2 11) X = A + B (5 6 7 0) (3 7 1 9)What do x
_{2,3}and x_{1,4}represent? Give your answer in the form x_{2,3}, x_{1,4}. - 8.For addition to be possible, two matrices must have the same __________. For multiplication to be possible, the number of __________ in the first matrix must be the same as the number of __________ in the second matrix. The resultant matrix would have the number of __________ the first matrix has, and the number of ___________ the second matrix has.Fill in the above blanks, with a comma and a space in between succeding answers.
- 9.A = 3 (1 2 8) B = (5) (7 4 9)Evaluate A and B and present your answers as A, B with two spacings between each entry in each matrix.
- 10.A = (4 9 8 2 1) (2) (9) B = (2) (3) (4)Evaluate AB and BA and present your answers as AB, BA.