Question

For which of the following matrices it is possible to find a determinant?

• A. $\left[\begin{array}{cccc}1& 2& 3& 4\\ 5& 6& 7& 8\\ 9& 10& 11& 2\end{array}\right]$
• B. $\left[\begin{array}{ccc}1& 2& 3\\ 4& 5& 6\end{array}\right]$
• C. $\left[\begin{array}{ccc}1& 2& 3\\ 4& 5& 6\\ 7& 8& 9\end{array}\right]$
• D. $\left[\begin{array}{cccc}1& 2& 3& 2\\ 4& 5& 6& 8\end{array}\right]$

Answer 1

The correct option is C $\left[\begin{array}{ccc}1& 2& 3\\ 4& 5& 6\\ 7& 8& 9\end{array}\right]$

Since determinant is defined only for square matrices. So it can be found for the matrix given in option c. only. Rest all the matrices are not square matrices, i.e. their number of rows is not equal to the number of columns.