April 2026

Let A = [[3, 2, 7], [1, 4, 3], [-2, 5, 8]]. Find matrices X and Y such that X + Y = A, where X is a symmetric and Y is a skew-symmetric matrix.

Decompose Matrix into Symmetric and Skew-Symmetric Parts Find Symmetric and Skew-Symmetric Matrices X and Y Given: \[ A = \begin{bmatrix} 3 & 2 & 7 \\ 1 & 4 & 3 \\ -2 & 5 & 8 \end{bmatrix} \] Formula Used: \[ X = \frac{1}{2}(A + A^T), \quad Y = \frac{1}{2}(A – A^T) \] Step […]

Let A = [[3, 2, 7], [1, 4, 3], [-2, 5, 8]]. Find matrices X and Y such that X + Y = A, where X is a symmetric and Y is a skew-symmetric matrix. Read More »

If l1, m1, n1 ; i=1,2,3 denote the direction cosines of three mutually perpendicular vectors in space, prove that AA^T = I, where A=[[l1, m1, m1], [l2, m2, n2], [l3, m3, n3]]

Prove AA^T = I using Direction Cosines Prove that AAT = I Given: \[ A = \begin{bmatrix} l_1 & m_1 & n_1 \\ l_2 & m_2 & n_2 \\ l_3 & m_3 & n_3 \end{bmatrix} \] where \((l_i, m_i, n_i)\) are direction cosines of three mutually perpendicular unit vectors. Properties Used: \[ l_i^2 + m_i^2

If l1, m1, n1 ; i=1,2,3 denote the direction cosines of three mutually perpendicular vectors in space, prove that AA^T = I, where A=[[l1, m1, m1], [l2, m2, n2], [l3, m3, n3]] Read More »

If A = [[sin α, cos α], [-cos α, sin α]], verify that A^T A = I2

Verify A^T A = I₂ Verify that ATA = I2 Given: \[ A = \begin{bmatrix} \sin\alpha & \cos\alpha \\ -\cos\alpha & \sin\alpha \end{bmatrix} \] Step 1: Find AT \[ A^T = \begin{bmatrix} \sin\alpha & -\cos\alpha \\ \cos\alpha & \sin\alpha \end{bmatrix} \] Step 2: Compute ATA \[ A^T A = \begin{bmatrix} \sin\alpha & -\cos\alpha \\ \cos\alpha

If A = [[sin α, cos α], [-cos α, sin α]], verify that A^T A = I2 Read More »

If A = [[cos α, sin α], [-sin α, cos α]], then verify that A^T A = I2.

Verify A^T A = I₂ Verify that ATA = I2 Given: \[ A = \begin{bmatrix} \cos\alpha & \sin\alpha \\ -\sin\alpha & \cos\alpha \end{bmatrix} \] Step 1: Find AT \[ A^T = \begin{bmatrix} \cos\alpha & -\sin\alpha \\ \sin\alpha & \cos\alpha \end{bmatrix} \] Step 2: Compute ATA \[ A^T A = \begin{bmatrix} \cos\alpha & -\sin\alpha \\ \sin\alpha

If A = [[cos α, sin α], [-sin α, cos α]], then verify that A^T A = I2. Read More »

For the matrices, A and B, verify that (AB)^T = B^TA^T, where A = [[1, 3], [2, 4]], B = [[1, 4], [2, 5]]

Verify (AB)^T = B^T A^T Verify that (AB)T = BTAT Given: \[ A = \begin{bmatrix} 1 & 3 \\ 2 & 4 \end{bmatrix}, \quad B = \begin{bmatrix} 1 & 4 \\ 2 & 5 \end{bmatrix} \] To Verify: \[ (AB)^T = B^T A^T \] Step 1: Find AB \[ AB = \begin{bmatrix} 1 & 3

For the matrices, A and B, verify that (AB)^T = B^TA^T, where A = [[1, 3], [2, 4]], B = [[1, 4], [2, 5]] Read More »