Mathematics – Class 12 – Multiple Choice Type Questions – by O P Gupta

, By O.P. GUPTA
Indira Award Winner
M.+919650350480




Chapter 01 - Matrices & Determinants
 Select the correct option (s) in the followings.
Q01. If A and B are two matrices such that A  B and AB are both defined then
(a) A and B can be any matrices
(b) A and B are square matrices not necessarily of same order
(c) Number of columns in A  Number of rows in B
(d) A and B are square matrices of same order.
 2 1
Q02. If A    then, AA T is equal to
3 1 
 5 5 1 1  1 1 
(a)   (b) 5   (c) 5 I 2 (d)  
10 5 1 2  1 2 
a b c
Q03. Let A  d e f  4 . Then adj.A 
g h i
(a) 16 (b) 2 only (c) –2 only (d) –16
x 2 
Q105. If   is a singular matrix, then the product of all possible values of x is
 3 x  1
(a) 6 (b) 6 (c) 0 (d) 7
1
A 1
Q106. If  , where A is a 3  3 matrix, then the value of k is
2 kA
1 1
(a) (b) 8 (c) 2 (d)
8 2
0 1
Q107. If A    , then A 2023 is equal to
0 0
 0 1  0 2023  0 0  2023 0 
(a)   (b) 0 (c) (d)
 0 0  0   0 0
 
 0
 2023
 2 0
Q108. If 
5 4   P  Q, where P is a symmetric and Q is a skew symmetric matrix, then Q 
 
 2 5/2   0 5/2   0 5/2   2 5/2 
(a)   (b)   (c)   (d) 
5/2 4  5/2 0   5/2 0  5/2 4 
Q110. If A  kA , where A is a square matrix of order 2, then sum of all possible value of k is
(a) 1 (b) 1 (c) 2 (d) 0
Q111. Number of symmetric matrices of order 3  3 with each entry 1 or –1 is
(a) 512 (b) 64 (c) 8 (d) 4

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