Q39 / 120 · NDA 2024 (Phase 2) · Mathematics
What is the number of real roots of the equation $(x-1)^2$ $+(x-3)^2+(x-5)^2=0 ?$
- Correct answerANone
- BOnly one
- COnly two
- DThree
Solution
Given that, $(x-1)^2+(x-3)^2+(x-5)^2=0$
$\begin{aligned}
& \Rightarrow x^2-2 x+1+x^2-6 x+9+x^2-10 x+25=0 \\
& \Rightarrow 3 x^2-18 x+35=0
\end{aligned}$
Discriminant $\mathrm{D}=(-18)^2-4 \times 3 \times 35=-96 < 0$
$\because$ Discriminant is negative. So, the given equation does not have any real roots.
Hence, the correct answer is option: 'A'.