What is a symmetric matrix? A symmetric matrix is a matrix which is transpose of itself. In other words, if A is a square matrix such that AT = A, then A is a symmetric matrix. Let’s look at an example. Let’s say A is a 3x3 square matrix with the following elements....

What is a lower triangular matrix? A lower triangular matrix is a square matrix in which all the elements above the principal diagonal are zero. For example, the matrix A given below is a lower triangular matrix. $latex A=\begin{bmatrix} a_{1,1} & 0 & ... & 0 \\...

What is an upper triangular matrix? An upper triangular matrix is a square matrix in which all the elements below the principal diagonal are zeros. For example, the matrix A given below is an nxn square matrix that is upper triangular. $latex A=\begin{bmatrix} a_{1,1}...

What is a diagonal matrix? A diagonal matrix is a square matrix in which all elements other than the elements in the principal diagonal are zero. So, if A is a square matrix and Ai,j is the element in the ith row and jth column, then $latex A_{i,j}=0\ where\ i \neq j...

What is an identity matrix? An identity matrix is a square matrix or an nxn matrix that contains ones in its main diagonal and all other elements are zero. For example, let’s say I3 is an identity matrix with 3 rows and 3 columns. So, I3 will contain the following...