# Topic: Chapter 1: Applications of Matrices and Determinants (Test 1)

Topic: Chapter 1: Applications of Matrices and Determinants
Q.1
If | adj(adj A) |=| A |9 , then the order of the square matrix A is
A. 3
B. 4
C. 2
D. 5
Answer : Option B
Explaination / Solution:

Workspace
Report
Q.2
If A is a 3× 3 non-singular matrix such that AAT = AT A and B = A1 AT , then BBT =
A. A
B. B
C. I3
D. BT
Answer : Option C
Explaination / Solution:

Workspace
Report
Q.3
If A =  , B = adj A and C = 3A , then  =
A. 1/3
B. 1/9
C. 1/4
D. 1
Answer : Option B
Explaination / Solution:

Workspace
Report
Q.4
if , then A =
A.
B.
C.
D.
Answer : Option C
Explaination / Solution:

Workspace
Report
Q.5
if , then 9I2 – A =
A. A-1
B. A-1/2
C. 3A-1
D. 2A-1
Answer : Option D
Explaination / Solution:

Workspace
Report
Q.6
if A = , B=  then | adj ( AB) |=
A. -40
B. -80
C. -60
D. -20
Answer : Option B
Explaination / Solution:

Workspace
Report
Q.7
If P=  is the adjoint of 3× 3 matrix A and | A |= 4 , then x is
A. 15
B. 12
C. 14
D. 11
Answer : Option D
Explaination / Solution:

Workspace
Report
Q.8
If A , and A1  then the value of a23 is
A. 0
B. -2
C. -3
D. -1
Answer : Option D
Explaination / Solution:

Workspace
Report
Q.9
If A, B and C are invertible matrices of some order, then which one of the following is not true?
A. adj A =| A | A-1
C. det A-1 = (det A)-1
D. ( ABC)-1 = C-1B-1A-1
Answer : Option B
Explaination / Solution:

Workspace
Report
Q.10
If ( AB)1 , and A-1, then B1 =
A.
B.
C.
D.
Answer : Option A
Explaination / Solution:

Workspace
Report