The matrix $\begin{bmatrix} 1 & 0 & 0 \\ 0 & 2 & 0 \\ 0 & 0 & 4 \end{bmatrix}$ is a

symmetric matrix

The correct answer is Option (2) → symmetric matrix ##

Let $A = \begin{bmatrix} 1 & 0 & 0 \\ 0 & 2 & 0 \\ 0 & 0 & 4 \end{bmatrix}$

$∴$ $A' = \begin{bmatrix} 1 & 0 & 0 \\ 0 & 2 & 0 \\ 0 & 0 & 4 \end{bmatrix} = A$

So, the given matrix is a symmetric matrix.

[since, for a square matrix $A$, if $A' = A$, then $A$ is called symmetric matrix]