11. If A and B are matrices of orders 4 × 5 and 5 × 7 respectively, then the order of AB is:
A. 5 × 5
B. 4 × 7
C. 5 × 4
D. 7 × 5
152. If A and B are two nonzero matrices. Is it possible to have AB = 0?
A. Yes
B. No
13. Which law does not hold in matrices?
A. Associative law of multiplication
B. Distributive law of multiplication over addition
C. Cancellation law
D. Both A and B
14. If the matrices A, B and C are conformable for the sums and multiplications, then which
of the following is correct?
A. A(BC) = (AB)C
B. A(B + C) = AB + AC
C. k(AB) = (kA)B
D. All of these
15. If order of A is 8 × 7, then the order of AAt
is:
A. 7 × 8
B. 7 × 7
C. 8 × 8
D. Product is not possible
16. If the matrices A and B are conformable for the sum and the product, then:
A. (AB)
t = B^tA^t
B. (A^t)^t = A
C. (kA)^t = kAt
D. All of these
17. A square matrix A for which A^k+1 = A, (k being a positive integer), is called a …
matrix.
A. Nilpotent
B. Periodic
C. Involutory
D. Idempotent
18. If A^6 = A, then the period of A is:
A. 5
B. 6
C. 7
D. Not period
19. A matrix of period 1 is:
A. Nilpotent
B. Involutory
C. Idempotent
D. Involutory
20. A square matrix A for which A^p = 0 (p being a positive integer), is called …
A. Nilpotent
B. Involutory
C. Idempotent
D. Involutory
