Advertisements
Advertisements
प्रश्न
If B is a skew-symmetric matrix, write whether the matrix AB AT is symmetric or skew-symmetric.
उत्तर
If B is a skew-symmetric matrix, then
\[\left( AB A^T \right)^T = \left( A^T \right)^T B^T A^T \left[ \because \left( ABC \right)^T = C^T B^T A^T \right]\]
\[ \Rightarrow \left( AB A^T \right)^T = A B^T A^T \left[ \because \left( A^T \right)^T = A \right]\]
\[ \Rightarrow \left( AB A^T \right)^T = A\left( - B \right) A^T \left[ \because B^T = - B \right]\]
\[ \Rightarrow \left( AB A^T \right)^T = - AB A^T \]
APPEARS IN
संबंधित प्रश्न
Write the element a12 of the matrix A = [aij]2 × 2, whose elements aij are given by aij = e2ix sin jx.
Find the maximum value of `|(1,1,1),(1,1+sintheta,1),(1,1,1+costheta)|`
Write the element a23 of a 3 ✕ 3 matrix A = (aij) whose elements aij are given by `a_(ij)=∣(i−j)/2∣`
Let A be a matrix of order 3 × 4. If R1 denotes the first row of A and C2 denotes its second column, then determine the orders of matrices R1 and C2
Construct a 2 × 2 matrix whose elements `a_(ij)`
are given by: `(i+j)^2/2`
Construct a 2 × 2 matrix whose elements aij are given by:
`aij=(i-j)^2/2`
Construct a 2 × 2 matrix whose elements aij are given by:
`a_(ij)=(i-2_j)^2/2`
Construct a 2 × 2 matrix whose elements aij are given by:
`a_(ij)= (2i +j)^2/2`
Construct a 2 × 2 matrix whose elements aij are given by:
`a_(ij)=|2_i - 3_i|/2`
Construct a 2 × 2 matrix whose elements aij are given by:
`a_(ij)=|-3i +j|/2`
Construct a 2 × 2 matrix whose elements aij are given by:
`a_(ij)=e^(2ix) sin (xj)`
Construct a 3 × 4 matrix A = [aij] whose elements aij are given by:
aij = i + j
Construct a 3 × 4 matrix A = [aij] whose elements aij are given by:
aij = 2i
Construct a 4 × 3 matrix whose elements are
`a_(ij)=2_i+ i/j`
Given an example of
a triangular matrix
The sales figure of two car dealers during January 2013 showed that dealer A sold 5 deluxe, 3 premium and 4 standard cars, while dealer B sold 7 deluxe, 2 premium and 3 standard cars. Total sales over the 2 month period of January-February revealed that dealer A sold 8 deluxe 7 premium and 6 standard cars. In the same 2 month period, dealer B sold 10 deluxe, 5 premium and 7 standard cars. Write 2 × 3 matrices summarizing sales data for January and 2-month period for each dealer.
If `A=[[cos θ, i sinθ],[i sinθ,cosθ]]` then prove by principle of mathematical induction that `A^n=[[cos nθ,i sinθ],[i sin nθ,cos nθ]]` for all `n ∈ N.`
If A = diag (a, b, c), show that An = diag (an, bn, cn) for all positive integer n.
If A is a square matrix, using mathematical induction prove that (AT)n = (An)T for all n ∈ ℕ.
If A and B are symmetric matrices, then write the condition for which AB is also symmetric.
If B is a symmetric matrix, write whether the matrix AB AT is symmetric or skew-symmetric.
If A is a skew-symmetric and n ∈ N such that (An)T = λAn, write the value of λ.
If A is a skew-symmetric matrix and n is an odd natural number, write whether An is symmetric or skew-symmetric or neither of the two.
If A is a skew-symmetric matrix and n is an even natural number, write whether An is symmetric or skew symmetric or neither of these two.
If \[\begin{bmatrix}x & 1\end{bmatrix}\begin{bmatrix}1 & 0 \\ - 2 & 0\end{bmatrix} = O\] , find x.
Matrix A = \[\begin{bmatrix}0 & 2b & - 2 \\ 3 & 1 & 3 \\ 3a & 3 & - 1\end{bmatrix}\] is given to be symmetric, find values of a and b.
If the matrix AB is zero, then
If \[A = \begin{bmatrix}5 & x \\ y & 0\end{bmatrix}\] and A = AT, then
If A is 3 × 4 matrix and B is a matrix such that A'B and BA' are both defined. Then, B is of the type
If \[A = \begin{bmatrix}\cos \theta & - \sin \theta \\ \sin \theta & \cos \theta\end{bmatrix}\] then AT + A = I2, if