The value of \(x\) for which \(\left|\begin{array}{ll}3&x\\ x&1\end{array}\right|=\left|\begin{array}{ll}3&2\\ 4&1\end{array}\right|\) is
Answer & explanation
Correct answer: option 3
\(\left|\begin{array}{ll}3&x\\ x&1\end{array}\right|=\left|\begin{array}{ll}3&2\\ 4&1\end{array}\right|⇒3-x^2=3-8\)
$⇒x^2=8$
$⇒x=±2\sqrt{2}$