Question:medium
If
\[
\begin{pmatrix}
a & b \\
c & d
\end{pmatrix}
\]
is the inverse of the matrix
\[
\begin{pmatrix}
1 & 5 \\
7 & -3
\end{pmatrix},
\]
then \( d \) equals
If
\[
\begin{pmatrix}
a & b \\
c & d
\end{pmatrix}
\]
is the inverse of the matrix
\[
\begin{pmatrix}
1 & 5 \\
7 & -3
\end{pmatrix},
\]
then \( d \) equals
Show Hint
Inverse of \(2\times2\): swap diagonal elements and change signs of off-diagonal entries.
Updated On: Apr 30, 2026
- \( -\frac{1}{38} \)
- \( -\frac{7}{38} \)
- \( \frac{3}{38} \)
- \( \frac{5}{38} \)
- \( \frac{9}{38} \)
Show Solution
The Correct Option is A
Solution and Explanation
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