Question
Out of the given matrices, choose that matrix which is a scalar matrix:

  1. $\begin{bmatrix}0&0\\0&0\end{bmatrix}$

  2. $\begin{bmatrix}0&0&0\\0&0&0\end{bmatrix}$

  3. $\begin{bmatrix}0&0\\0&0\\0&0\end{bmatrix}$

  4. $\begin{bmatrix}0\\0\\0\end{bmatrix}$

Answer

  1. $\begin{bmatrix}0&0\\0&0\end{bmatrix}$

Solution:

A diagonal matrix with all diagonal elements are equal is a scalar matrix.

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