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Matrices

Each subtopic includes About section, revision page link, 10 preview questions, and practice CTAs.

Concept, notation, order, equality, types of matrices, zero and identity matrix

Subtopic

Concept, notation, order, equality, types of matrices, zero and identity matrix under Matrices for Grade 12 CBSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    Two matrices Am×nA_{m \times n} and Bp×qB_{p \times q} can be equal only if:

    A.

    m=pm=p and n=qn=q

    B.

    m=qm=q and n=pn=p

    C.

    m×n=p×qm \times n = p \times q

    D.

    m=nm=n and p=qp=q

  2. 2.

    The zero matrix of order 2×32 \times 3 is written as:

    A.

    [000000]\begin{bmatrix} 0 & 0 \\ 0 & 0 \\ 0 & 0 \end{bmatrix}

    B.

    [000000]\begin{bmatrix} 0 & 0 & 0 \\ 0 & 0 & 0 \end{bmatrix}

    C.

    [00]\begin{bmatrix} 0 & 0 \end{bmatrix}

    D.

    [000]\begin{bmatrix} 0 \\ 0 \\ 0 \end{bmatrix}

  3. 3.

    For a matrix A=[aij]4×3A = [a_{ij}]_{4 \times 3}, what is the maximum value of ii?

    A.

    3

    B.

    4

    C.

    12

    D.

    7

Download the worksheet for Matrices - Concept, notation, order, equality, types of matrices, zero and identity matrix to practice offline. It includes additional chapter-level practice questions.

Transpose of a matrix, symmetric and skew symmetric matrices

Subtopic

Transpose of a matrix, symmetric and skew symmetric matrices under Matrices for Grade 12 CBSE.

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Preview questions (no answers)

  1. 1.

    If A=[1234]A = \begin{bmatrix} 1 & 2 \\ 3 & 4 \end{bmatrix}, then its transpose A′A' is:

    A.

    [1324]\begin{bmatrix} 1 & 3 \\ 2 & 4 \end{bmatrix}

    B.

    [4321]\begin{bmatrix} 4 & 3 \\ 2 & 1 \end{bmatrix}

    C.

    [1234]\begin{bmatrix} 1 & 2 \\ 3 & 4 \end{bmatrix}

    D.

    [2143]\begin{bmatrix} 2 & 1 \\ 4 & 3 \end{bmatrix}

  2. 2.

    For any square matrix AA, the matrix 12(A−A′)\frac{1}{2}(A - A') is always:

    A.

    Symmetric

    B.

    Skew-symmetric

    C.

    Identity

    D.

    Unitary

  3. 3.

    If A=[5665]A = \begin{bmatrix} 5 & 6 \\ 6 & 5 \end{bmatrix}, then A−A′A - A' is equal to:

    A.

    II

    B.

    2A2A

    C.

    [0000]\begin{bmatrix} 0 & 0 \\ 0 & 0 \end{bmatrix}

    D.

    [10121210]\begin{bmatrix} 10 & 12 \\ 12 & 10 \end{bmatrix}

Download the worksheet for Matrices - Transpose of a matrix, symmetric and skew symmetric matrices to practice offline. It includes additional chapter-level practice questions.

Operation on matrices: Addition, multiplication and multiplication with a scalar

Subtopic

Operation on matrices: Addition, multiplication and multiplication with a scalar under Matrices for Grade 12 CBSE.

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Preview questions (no answers)

  1. 1.

    If X + $$\begin{bmatrix} 1 & 2 \\ 3 & 4 \end{bmatrix}$$ = \begin{bmatrix} 0 & 0 \\ 0 & 0 \end{bmatrix}, then XX is:

    A.

    [1234]\begin{bmatrix} 1 & 2 \\ 3 & 4 \end{bmatrix}

    B.

    [−1−2−3−4]\begin{bmatrix} -1 & -2 \\ -3 & -4 \end{bmatrix}

    C.

    [0000]\begin{bmatrix} 0 & 0 \\ 0 & 0 \end{bmatrix}

    D.

    [4321]\begin{bmatrix} 4 & 3 \\ 2 & 1 \end{bmatrix}

  2. 2.

    If A=[1201]A = \begin{bmatrix} 1 & 2 \\ 0 & 1 \end{bmatrix} and B=[2002]B = \begin{bmatrix} 2 & 0 \\ 0 & 2 \end{bmatrix}, then ABAB is:

    A.

    [2402]\begin{bmatrix} 2 & 4 \\ 0 & 2 \end{bmatrix}

    B.

    [2202]\begin{bmatrix} 2 & 2 \\ 0 & 2 \end{bmatrix}

    C.

    [3203]\begin{bmatrix} 3 & 2 \\ 0 & 3 \end{bmatrix}

    D.

    [2002]\begin{bmatrix} 2 & 0 \\ 0 & 2 \end{bmatrix}

  3. 3.

    If A=[12]A = \begin{bmatrix} 1 \\ 2 \end{bmatrix} and B=[34]B = \begin{bmatrix} 3 & 4 \end{bmatrix}, the order of ABAB is:

    A.

    1×11 \times 1

    B.

    2×22 \times 2

    C.

    1×21 \times 2

    D.

    2×12 \times 1

Download the worksheet for Matrices - Operation on matrices: Addition, multiplication and multiplication with a scalar to practice offline. It includes additional chapter-level practice questions.

Simple properties of addition, multiplication and scalar multiplication

Subtopic

Simple properties of addition, multiplication and scalar multiplication under Matrices for Grade 12 CBSE.

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Preview questions (no answers)

  1. 1.

    If A=[aij]A = [a_{ij}] is a square matrix such that aij=0a_{ij} = 0 for i≠ji \neq j, it is called a:

    A.

    Diagonal matrix

    B.

    Row matrix

    C.

    Column matrix

    D.

    Scalar matrix

  2. 2.

    A matrix having only one column is called a:

    A.

    Row matrix

    B.

    Column matrix

    C.

    Identity matrix

    D.

    Zero matrix

  3. 3.

    If A=[1234]A = \begin{bmatrix} 1 & 2 \\ 3 & 4 \end{bmatrix}, then A+AA + A is:

    A.

    [2468]\begin{bmatrix} 2 & 4 \\ 6 & 8 \end{bmatrix}

    B.

    [14916]\begin{bmatrix} 1 & 4 \\ 9 & 16 \end{bmatrix}

    C.

    [2234]\begin{bmatrix} 2 & 2 \\ 3 & 4 \end{bmatrix}

    D.

    [0000]\begin{bmatrix} 0 & 0 \\ 0 & 0 \end{bmatrix}

Download the worksheet for Matrices - Simple properties of addition, multiplication and scalar multiplication to practice offline. It includes additional chapter-level practice questions.

Invertible matrices and proof of the uniqueness of inverse

Subtopic

Invertible matrices and proof of the uniqueness of inverse under Matrices for Grade 12 CBSE.

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Preview questions (no answers)

  1. 1.

    The uniqueness of the inverse theorem states that if a matrix has an inverse, it has:

    A.

    Exactly one inverse

    B.

    At least two inverses

    C.

    Infinite inverses

    D.

    No inverse

  2. 2.

    If a square matrix AA has an inverse BB, then the product of their determinants ∣A∣⋅∣B∣|A| \cdot |B| is:

    A.

    00

    B.

    11

    C.

    −1-1

    D.

    ∣A∣|A|

  3. 3.

    If AA is an invertible matrix and k=−1k = -1, then (−A)−1(-A)^{-1} is equal to:

    A.

    A−1A^{-1}

    B.

    −A−1-A^{-1}

    C.

    AA

    D.

    −A-A

Download the worksheet for Matrices - Invertible matrices and proof of the uniqueness of inverse to practice offline. It includes additional chapter-level practice questions.

Order of a matrix

Subtopic

Order of a matrix under Matrices for Grade 12 CBSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    For a matrix [aij]2×3[a_{ij}]_{2 \times 3}, what is the maximum value jj can take?

    A.

    1

    B.

    2

    C.

    3

    D.

    6

  2. 2.

    If a matrix AA has 8 elements, which of these is NOT a possible order?

    A.

    1×81 \times 8

    B.

    2×42 \times 4

    C.

    4×24 \times 2

    D.

    3×33 \times 3

  3. 3.

    What is the order of a matrix with mm rows and nn columns?

    A.

    n×mn \times m

    B.

    m×nm \times n

    C.

    m+nm+n

    D.

    mnmn

Download the worksheet for Matrices - Order of a matrix to practice offline. It includes additional chapter-level practice questions.

Equality of matrices

Subtopic

Equality of matrices under Matrices for Grade 12 CBSE.

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Preview questions (no answers)

  1. 1.

    Two matrices AA and BB are equal. If the order of AA is 2×32 \times 3, what must be the order of BB?

    A.

    3×23 \times 2

    B.

    2×22 \times 2

    C.

    3×33 \times 3

    D.

    2×32 \times 3

  2. 2.

    If [x3]=[8]\begin{bmatrix} x^3 \end{bmatrix} = \begin{bmatrix} 8 \end{bmatrix}, find the real value of xx.

    A.

    8

    B.

    4

    C.

    2

    D.

    64

  3. 3.

    If [123]=[x−1y−2z−3]\begin{bmatrix} 1 \\ 2 \\ 3 \end{bmatrix} = \begin{bmatrix} x - 1 \\ y - 2 \\ z - 3 \end{bmatrix}, find the value of xx.

    A.

    0

    B.

    1

    C.

    2

    D.

    3

Download the worksheet for Matrices - Equality of matrices to practice offline. It includes additional chapter-level practice questions.

Properties of matrix addition

Subtopic

Properties of matrix addition under Matrices for Grade 12 CBSE.

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Preview questions (no answers)

  1. 1.

    Is the sum of two 2×22 \times 2 identity matrices equal to the 2×22 \times 2 identity matrix?

    A.

    Yes, always

    B.

    No, it is equal to 2I2I

    C.

    No, it is equal to the zero matrix

    D.

    Only if the matrices are singular

  2. 2.

    If A+B=CA + B = C, then C−BC - B is equal to:

    A.

    −A-A

    B.

    BB

    C.

    AA

    D.

    OO

  3. 3.

    What is the element in the 2nd row and 1st column of the sum of [1234]\begin{bmatrix} 1 & 2 \\ 3 & 4 \end{bmatrix} and [5678]\begin{bmatrix} 5 & 6 \\ 7 & 8 \end{bmatrix}?

    A.

    6

    B.

    8

    C.

    10

    D.

    12

Download the worksheet for Matrices - Properties of matrix addition to practice offline. It includes additional chapter-level practice questions.

Properties of scalar multiplication of a matrix

Subtopic

Properties of scalar multiplication of a matrix under Matrices for Grade 12 CBSE.

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Preview questions (no answers)

  1. 1.

    If k(A+B)=kA+kBk(A+B) = kA + kB, and k=0k=0, the result is always:

    A.

    The zero matrix OO

    B.

    The matrix A+BA+B

    C.

    The identity matrix II

    D.

    The matrix AA

  2. 2.

    If AA is a null matrix, then 100A100A is:

    A.

    A null matrix

    B.

    An identity matrix

    C.

    A matrix with all elements 100

    D.

    A diagonal matrix

  3. 3.

    Given A=[2−2]A = \begin{bmatrix} 2 & -2 \end{bmatrix} and B=[−11]B = \begin{bmatrix} -1 & 1 \end{bmatrix}, find 2A+4B2A + 4B.

    A.

    [00]\begin{bmatrix} 0 & 0 \end{bmatrix}

    B.

    [1−1]\begin{bmatrix} 1 & -1 \end{bmatrix}

    C.

    [8−8]\begin{bmatrix} 8 & -8 \end{bmatrix}

    D.

    [4−4]\begin{bmatrix} 4 & -4 \end{bmatrix}

Download the worksheet for Matrices - Properties of scalar multiplication of a matrix to practice offline. It includes additional chapter-level practice questions.

Properties of multiplication of matrices

Subtopic

Properties of multiplication of matrices under Matrices for Grade 12 CBSE.

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Preview questions (no answers)

  1. 1.

    If AA is a 2×22 \times 2 matrix such that A2=OA^2 = O, what is A3A^3?

    A.

    AA

    B.

    II

    C.

    OO

    D.

    A2A^2

  2. 2.

    If AA is a 3×43 \times 4 matrix and BB is a 4×24 \times 2 matrix, what is the element in the 1st row and 2nd column of ABAB formed by?

    A.

    Multiplying 1st row of AA with 2nd column of BB

    B.

    Multiplying 2nd row of AA with 1st column of BB

    C.

    Multiplying 1st row of AA with 1st row of BB

    D.

    Multiplying 2nd column of AA with 2nd row of BB

  3. 3.

    What is the expression for (A+B)2−(A−B)2(A+B)^2 - (A-B)^2 for square matrices AA and BB?

    A.

    4AB4AB

    B.

    2AB+2BA2AB + 2BA

    C.

    OO

    D.

    A2−B2A^2 - B^2

Download the worksheet for Matrices - Properties of multiplication of matrices to practice offline. It includes additional chapter-level practice questions.

Properties of transpose of the matrices

Subtopic

Properties of transpose of the matrices under Matrices for Grade 12 CBSE.

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Preview questions (no answers)

  1. 1.

    If A=[5]A = [5], what is A′A'?

    A.

    [−5][-5]

    B.

    [1/5][1/5]

    C.

    [5][5]

    D.

    [0][0]

  2. 2.

    For any square matrix AA, what is the transpose of AnA^n?

    A.

    nA′n A'

    B.

    (A′)n(A')^n

    C.

    AA

    D.

    n2An^2 A

  3. 3.

    If A′A' has order 5×25 \times 2, what is the order of matrix AA?

    A.

    5×25 \times 2

    B.

    2×52 \times 5

    C.

    5×55 \times 5

    D.

    2×22 \times 2

Download the worksheet for Matrices - Properties of transpose of the matrices to practice offline. It includes additional chapter-level practice questions.

Symmetric and Skew Symmetric Matrices

Subtopic

Symmetric and Skew Symmetric Matrices under Matrices for Grade 12 CBSE.

About Topic & Revision

Preview questions (no answers)

  1. 1.

    If AA is a skew-symmetric matrix, what is the trace of AA?

    A.

    1

    B.

    Order of matrix nn

    C.

    0

    D.

    Sum of all elements

  2. 2.

    If AA is a symmetric matrix, then A+IA + I is a:

    A.

    Skew-symmetric matrix

    B.

    Identity matrix

    C.

    Symmetric matrix

    D.

    Null matrix

  3. 3.

    If A=[abcd]A = \begin{bmatrix} a & b \\ c & d \end{bmatrix} is skew-symmetric, then the value of a+da+d is:

    A.

    1

    B.

    2

    C.

    0

    D.

    b+cb+c

Download the worksheet for Matrices - Symmetric and Skew Symmetric Matrices to practice offline. It includes additional chapter-level practice questions.