Question

If $\left[\begin{array}{cccc}1& 0& 0& 0\\ 2& 3& 0& 0\\ 4& 5& 6& 0\\ 7& 8& 9& 10\end{array}\right]$, then A is

• A. An upper triangular matrix
• B. A null matrix
• C. A lower triangular matrix
• D. None of these

Answer 1

The correct option is C A lower triangular matrix

Since a square matrix A whose elements $a_{ij}=0$ for i < j. Then A is the lower triangular matrix.