Question

Find the determinant of $\left[\begin{array}{ccc}2&1\\1&-5\end{array}\right]$

Answer 1

Answer:

$\text {Determinant =} -11$

Step-by-step explanation:

$\text {Find the determinant of }\left[\begin{array}{ccc}2&1\\1&-5\end{array}\right]$

$\text {Determinant =}\left|\begin{array}{ccc}2&1\\1&-5\end{array}\right|$

$\text {Determinant =}(2 \times (-5)) - (1 \times 1)$

$\text {Determinant =}-10 -1$

$\text {Determinant =} -11$