Search any question & find its solution
Question:
Answered & Verified by Expert
Under which of the following condition(s) does(do) the system of equations $\left(\begin{array}{ccc}1 & 2 & 4 \\ 2 & 1 & 2 \\ 1 & 2 & (a-4)\end{array}\right)\left(\begin{array}{l}x \\ y \\ z\end{array}\right)=\left(\begin{array}{l}6 \\ 4 \\ a\end{array}\right)$ possesses (possess) unique solution?
Options:
Solution:
2853 Upvotes
Verified Answer
The correct answer is:
$a \neq 8$
$\Delta \neq 0$
$\Rightarrow\left|\begin{array}{ccc}
1 & 2 & 4 \\
2 & 1 & 2 \\
1 & 2 & \mathrm{a}-4
\end{array}\right| \neq 0 \Rightarrow \mathrm{a} \neq 8$
$\Rightarrow\left|\begin{array}{ccc}
1 & 2 & 4 \\
2 & 1 & 2 \\
1 & 2 & \mathrm{a}-4
\end{array}\right| \neq 0 \Rightarrow \mathrm{a} \neq 8$
Looking for more such questions to practice?
Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.