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Time: 40minutes.
Type School name here Total marks = 30
Subject: Mathematics Obtain marks =
Name: Class: IX
Monthly Test Date: 13-Feb-2017
MCQ’s
1. Which of followings are Square Matrices?
I) [ 4 ]
4 0
[ ]
II) 0 2
1 5
III) [−39 31 ]
a) Only I b) I ∧II
c) Only III d) I ∧III
2. If the determinant of [−32 −51 ] is -7, then determinant of its additive inverse is
a) -7 b) 7
d) 0 e) -1
3. If [ 14 k0 ] is non-singular matrix, then
a) k ≠ 1 b) k ≠ 3
c) k ≠ 0 d) k ≠ 4
4. The order of matrix [ 42 5 2+a
−1 3−b ]
is
a) 2 ×4 b) 2 ×3
c) 4 ×2 d) 3 ×2
1 0 0
[
5. A= 0 −1 0 Is a
]
1
0 0 1
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a) Rectangular Matrix b) Scalar Matrix
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c) Identity Matrix d) Diagonal Matrix
6. If C= [02] and ¿ [ 2 0 ] , then CD is
4 0
a) [
0 0]
b) [ 40 04]
c) [ 0 4 ] d) [ 4 0 ]
7. Which of the following is Symmetric Matrix?
a) [ 21 12] b) [
2 1
1 −2 ]
2 −1 2 1
c) [
1 −2 ]
d) [
−1 2 ]
c 9
8. If A=[
2 3]
and determinant of A is 27 then c is
a) 15 b) -15
c) -9 d) 0
9. If two matrices A and B are defined as A=[ z ] and B=[ 2 3 ] then A × B is
a) [ 2 x 3x] b) [ 2 x +3 x ]
c) [ 23 xx ] d) Not possible
10. If X = [ 12 03] and Y is additive inverse of X then X −Y is
2 0 −1 0
a) [ ] b) [
4 6 −2 −3 ]
0 0 0 1
c) [ ] d) [
0 0 1 0]
a b 1 0
11. If P=[
c d]
andQ=[
0 1]
t
, then P ×Q is equal to
a b c b
a) [
c d]
b) [
d a]
0 d a 0
c) [
c 0]
d) [
0 b]
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3 x +1 5
12. If A= [ 2x 5
3 6 ]and B=
[ 18
6 ]
√36 and A=B, then x is equal to
a) 1 b) -1 c) 0 d) 9
13. Which of the following statement is not true?
a) Every Identity Matrix is Scalar Matrix.
b) Interchanging of rows and columns is known is transpose of Matrix.
c) Inverse of Singular matrix is possible.
d) Order of matrix cannot be negative.
14. Which of the following is not true?
a) A A−1 =I b) AI =A
t
c) ( At ) =− A d) A+ (− A )=O
15.If A− [−12 ]=−2[−20]
a) [−16 ] b) [−6
−1 ]
6 6
c) [ ] d) [ ]
1 0
CRO’s
Q.1. Given that the matrix A= [ 4c −15 ] and B=[ 16 −1 3
0 5
. ] (5marks)
1. Find the determinant of A in terms of c. (1mark)
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2. If A is singular matrix then evaluate the value of c. (2mark).
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3. Find if possible the transpose of matrix B× A. Give the reason to support your answer.
(1mark).
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4. Why can the determinant of the matrix B Not be determined? (1mark).
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5 7
−1
Q.2. If A = [ ]
2 3
, and | A|=1 , Then find matrix A. (3marks)
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Q.3. Prove that the product of matrix [ 21 −35 ] and its inverse is equal to unit matrix.
(4marks).
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Q.4. Solve the following system of equations by Cramer’s rule. (3marks)
2 x−3 y=3 , 5 x− y=1
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