## What is the dimension of Nxn symmetric matrices?

Let A denote the space of symmetric (n×n) matrices over the field K, and B the space of skew-symmetric (n×n) matrices over the field K. Then dim(A)=n(n+1)/2 and dim(B)=n(n−1)/2.

## What is symmetric and skew symmetric matrix with example?

A matrix is symmetric if and only if it is equal to its transpose. A matrix is skew-symmetric if and only if it is the opposite of its transpose. All main diagonal entries of a skew-symmetric matrix are zero.

**What is the dimension of the vector space of all 3×3 skew symmetric matrices?**

A basis is 1, x, x2, x3. Example: as we saw above, the dimension of the space of 3 × 3 skew-symmetric matrix is 3.

**What is symmetric matrix with example?**

A square matrix that is equal to its transpose is called a symmetric matrix. For example, a square matrix A = aij is symmetric if and only if aij= aji for all values of i and j, that is, if a12 = a21, a23 = a32, etc. Note that if A is a symmetric matrix then A’ = A where A’ is a transpose matrix of A.

### What is symmetric matrix and skew symmetric matrix?

A symmetric matrix is a matrix whose transpose is equal to the matrix itself whereas a skew symmetric matrix is a matrix whose transpose is equal to the negative of itself.

### How do you find the basis of a symmetric matrix?

by definition of symmetry, ai,j=aj,i. Therefore, the basis should consist n2−n2 matrices to determine each symmetric pair. In addition, it should also consist n matrices to determine each term in the diagonal. Therefore, the dimension of the vector space is n2+n2.

**Is skew-symmetric matrix?**

Answer: A matrix can be skew symmetric only if it happens to be square. In case the transpose of a matrix happens to be equal to the negative of itself, then one can say that the matrix is skew symmetric. Therefore, for a matrix to be skew symmetric, A’=-A.

**Can a matrix be both symmetric and skew symmetric?**

Thus, the zero matrices are the only matrix, which is both symmetric and skew-symmetric matrix.

#### What is skew Hermitian matrix with example?

When the conjugate transpose of a complex square matrix is equal to the negative of itself, then this matrix is called as skew hermitian matrix. If P is a complex square matrix and if it satisfies Pθ = -P then such matrix is termed as skew hermitian. It is noted that Pθ represents the conjugate transpose of matrix P.

#### Is a 2 A symmetric matrix?

we can see that the matrix above is symmetric because it is equal to its transpose.

**Is a symmetric matrix normal?**

A (real-valued) symmetric matrix is necessarily a normal matrix.

**What are the dimensions of a skew symmetric matrix?**

The skew-symmetric matrices have arbitrary elements on one side with respect to the diagonal, and those elements determine the other triangle of the matrix. So they are in number of (n 2 − n) / 2 = n (n − 1) / 2, (− n to remove the diagonal).

## Is the inverse of a skew symmetric matrix singular?

If A is a skew-symmetric matrix, which is also a square matrix, then the determinant of A should satisfy the below condition: The inverse of skew-symmetric matrix does not exist because the determinant of it having odd order is zero and hence it is singular.

## How to prove that a + a’is a square matrix?

From the Theorem 1, we know that (A + A′) is a symmetric matrix and (A – A′) is a skew-symmetric matrix. Since for any matrix A, (kA)′ = kA′, it follows that 1 / 2 (A+A′) is a symmetric matrix and 1 / 2 (A − A′) is a skew-symmetric matrix. Thus, any square matrix can be expressed as the sum of a symmetric and a skew-symmetric matrix.

**How do you know if a matrix is symmetric?**

To know if a matrix is symmetric, find the transpose of that matrix. If the transpose of that matrix is equal to itself, it is a symmetric matrix. Give an Example of a Matrix Which is Symmetric but not Invertible. A zero (square) matrix is one such matrix which is clearly symmetric but not invertible.