Question:
The value of the determinant
\[
\begin{vmatrix}
-2 & 5 \\
-4 & 1
\end{vmatrix}
\]
will be:
The value of the determinant
\[
\begin{vmatrix}
-2 & 5 \\
-4 & 1
\end{vmatrix}
\]
will be:
Show Hint
For 2x2 matrices, always apply the formula \( ad - bc \) directly to compute the determinant.
Updated On: Mar 3, 2025
- 16
- 18
- 15
- 13
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The Correct Option is A
Solution and Explanation
The determinant of a 2×2 matrix
\[
\begin{pmatrix} a & b \\ c & d \end{pmatrix}
\]
is given by:
\[
\text{Determinant} = ad - bc.
\]
Substituting the values:
\[
\text{Determinant} = (-2)(1) - (5)(-4) = -2 + 20 = 16.
\]
Hence, the correct answer is A) 16.
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