JAMB - Mathematics (2009 - No. 20)
If Q is\( \left[ \begin{array}{cc}
9 & -2 \\
-7 & 4 \\
\end{array} \right]\) , then |Q| is?
9 & -2 \\
-7 & 4 \\
\end{array} \right]\) , then |Q| is?
-50
-22
22
50
Explicació
Q = \( \left[ \begin{array}{ccc}
9 & -2 \\
-7 & 4 \\
\end{array} \right]\)
|Q| = 9x4 - (-2 x -7)
= 36 - 14
= 22
9 & -2 \\
-7 & 4 \\
\end{array} \right]\)
|Q| = 9x4 - (-2 x -7)
= 36 - 14
= 22