Mathematics · Complex Numbers
JEE Main 2026 — 6 April, Morning Shift — Question 24
Let the set of all values of k∈R such that the equation , has at least one solution, be the interval Then is equal to:
- Option A:Correct
- Option B:
- Option C:
- Option D:
Answer: A
Step-by-step solution
Put ⇒ Real part Imaginary part
\Rightarrow x^{2}+y^{2}+2 x-y+2 k=0 \end{gathered}$$ and $\mathrm{x}+2 \mathrm{y}+3 \mathrm{k}=0$ eliminating $x$ from (1) and (2) $5 \mathrm{y}^{2}+(12 \mathrm{k}-5) \mathrm{y}+9 \mathrm{k}^{2}-4 \mathrm{k}=0$ since $y \in R$ use $\mathrm{D} \geq 0$ $(12 \mathrm{k}-5)^{2}-4.5\left(9 \mathrm{k}^{2}-4 \mathrm{k}\right) \geq 0$ $\Rightarrow 36 \mathrm{k}^{2}+40 \mathrm{k}-25 \leq 0$ $\Rightarrow \alpha+\beta=\frac{-10}{9}$ $\Rightarrow 9(\alpha+\beta)=-10$Answer key and solution verified before publishing.
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- Exam
- JEE Main 2026
- Subject
- Mathematics
- Chapter
- Complex Numbers
- Topic
- Introduction to Complex Numbers