Q165 / 270 · NDA 2023 (Phase 2) · Mathematics
If $\left|\begin{array}{ccc}x^2-3 x & x-1 & x+3 \\ x+1 & -2 x & x-4 \\ x-3 & x+4 & 3 x\end{array}\right|=a x^4+b x^3+c x^2+d x+e$, then what is the value of $e$ ?
- A-1
- Correct answerB0
- C1
- D2
Solution
If we put $x=0$
$\left|\begin{array}{ccr}
0 & -1 & 3 \\
1 & 0 & -4 \\
-3 & 4 & 0
\end{array}\right|=0+0+0+0+\mathrm{e}$
it is skew-symmetric of order $3 \times 3$
$\Rightarrow \text { So, } \quad \mathrm{e}=0$
Hence, the correct answer is option: 'B'.