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Determinants — Maths STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceMathsDeterminants1 Mark
MCQ
Find the determinant of the matrix $\text{A}=\begin{bmatrix}9&8\\7&6\end{bmatrix}$ is:
  • A
    $-1$
  • B
    $1$
  • C
    $2$
  • ✓
    $-2$
✓

Answer

Correct option: D.
$-2$
Given that, $\text{A}=\begin{bmatrix}9&8\\7&6\end{bmatrix}$
$\Rightarrow\triangle=\begin{bmatrix}9&8\\7&6\end{bmatrix}$
$=9(6)-7(8)$
$=54-56$
$=-2$

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