Ravi Kant Kumar

If S = sij] is a scalar matrix such that sii = k and A is a square matrix of the same order, then AS = SA = ? (a) Ak (b) k+ A (c) kA (d) ks

Scalar Matrix Multiplication Property 📘 Question If \(S = [s_{ij}]\) is a scalar matrix such that \(s_{ii} = k\), and \(A\) is a square matrix of the same order, then: \[ AS = SA = \; ? \] (a) \(Ak\) (b) \(k + A\) (c) \(kA\) (d) \(kS\) ✏️ Step-by-Step Solution Step 1: Understand scalar […]

If S = sij] is a scalar matrix such that sii = k and A is a square matrix of the same order, then AS = SA = ? (a) Ak (b) k+ A (c) kA (d) ks Read More »

If A = [[α, β], [γ, -α]] is such that A^2 = I, then

Find Relation for A² = I 📘 Question If \[ A = \begin{bmatrix} \alpha & \beta \\ \gamma & -\alpha \end{bmatrix} \] and \(A^2 = I\), find the relation between \(\alpha, \beta, \gamma\). ✏️ Step-by-Step Solution Step 1: Compute \(A^2\) \[ A^2 = \begin{bmatrix} \alpha & \beta \\ \gamma & -\alpha \end{bmatrix} \begin{bmatrix} \alpha &

If A = [[α, β], [γ, -α]] is such that A^2 = I, then Read More »

If A = [[1, -1], [2, -1]], B = [[a, 1], [b, -1]] and (A + B)^2 = A^2 + B^2, then values of a and b are

Find a and b Using Matrix Identity 📘 Question If \[ A = \begin{bmatrix} 1 & -1 \\ 2 & -1 \end{bmatrix}, \quad B = \begin{bmatrix} a & 1 \\ b & -1 \end{bmatrix} \] and \[ (A + B)^2 = A^2 + B^2 \] Find the values of \(a\) and \(b\). ✏️ Step-by-Step Solution

If A = [[1, -1], [2, -1]], B = [[a, 1], [b, -1]] and (A + B)^2 = A^2 + B^2, then values of a and b are Read More »

If A = [[n, 0, 0], [0, n, 0], [0, 0, n] and B = [[a1, a2, a3], [b1, b2, b3], [c1, c2, c3]], then AB is equal to

Find AB for Scalar Matrix 📘 Question If \[ A = \begin{bmatrix} n & 0 & 0 \\ 0 & n & 0 \\ 0 & 0 & n \end{bmatrix} ,\quad B = \begin{bmatrix} a_1 & a_2 & a_3 \\ b_1 & b_2 & b_3 \\ c_1 & c_2 & c_3 \end{bmatrix} \] Find \(AB\).

If A = [[n, 0, 0], [0, n, 0], [0, 0, n] and B = [[a1, a2, a3], [b1, b2, b3], [c1, c2, c3]], then AB is equal to Read More »

If A, B are square matrices of order, 3, A is non-singular and AB = O, then B is a (a) null matrix (b) singular matrix (c) unit matrix (d) non-singular matrix

AB = O and A Non-Singular 📘 Question If \(A\) and \(B\) are square matrices of order 3 such that: \[ AB = O \] and \(A\) is non-singular, then \(B\) is: (a) null matrix (b) singular matrix (c) unit matrix (d) non-singular matrix ✏️ Step-by-Step Solution Step 1: Use inverse of non-singular matrix Since

If A, B are square matrices of order, 3, A is non-singular and AB = O, then B is a (a) null matrix (b) singular matrix (c) unit matrix (d) non-singular matrix Read More »

If the matrix AB is zero, then (a) It is not necessary that either A =O or, B=O (b) A = O or B = O (c) A = O and B = O (d) all the above statements are wrong

AB = O Matrix Concept 📘 Question If \[ AB = O \] then which of the following is correct? (a) It is not necessary that either \(A = O\) or \(B = O\) (b) \(A = O\) or \(B = O\) (c) \(A = O\) and \(B = O\) (d) All the above statements

If the matrix AB is zero, then (a) It is not necessary that either A =O or, B=O (b) A = O or B = O (c) A = O and B = O (d) all the above statements are wrong Read More »

If [[cos2π/7, -sin2π/7], [sin2π/7, cos2π/7]]^k = [[1, 0], [0, 1]], then the least positive integral value of k is

Find Least k for Rotation Matrix 📘 Question If \[ \left[ \begin{array}{cc} \cos\frac{2\pi}{7} & -\sin\frac{2\pi}{7} \\ \sin\frac{2\pi}{7} & \cos\frac{2\pi}{7} \end{array} \right]^k = \begin{bmatrix} 1 & 0 \\ 0 & 1 \end{bmatrix} \] Find the least positive integer value of \(k\). ✏️ Step-by-Step Solution Step 1: Recognize the matrix This is a rotation matrix with angle:

If [[cos2π/7, -sin2π/7], [sin2π/7, cos2π/7]]^k = [[1, 0], [0, 1]], then the least positive integral value of k is Read More »