MCQ
If $\left|\begin{array}{ll}3 & 3 \\ x & 1\end{array}\right|=\left|\begin{array}{cc}-3 & x \\ 1 & 1\end{array}\right|$ then value of $x$ is :
- A2
- ✓3
- C-3
- D-2
✓
Answer
Correct option: B.
3
(B)$\quad\left|\begin{array}{ll}3 & 3 \\ x & 1\end{array}\right|=\left|\begin{array}{cc}-3 & x \\ 1 & 1\end{array}\right|$
$
\begin{aligned}
\Rightarrow & & 3-3 x & =-3-x \\
\Rightarrow & & 3+3 & =3 x-x \\
\Rightarrow & & 6 & =2 x \Rightarrow x=3
\end{aligned}
$
$
\begin{aligned}
\Rightarrow & & 3-3 x & =-3-x \\
\Rightarrow & & 3+3 & =3 x-x \\
\Rightarrow & & 6 & =2 x \Rightarrow x=3
\end{aligned}
$
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