Mathematics · Complex Numbers

JEE Main 2024 — 5 April, Shift 2 — Question 3

Let S1={z∈C:∣z∣≤5}S_{1}=\{z \in C:|z| \leq 5\}, S2={z∈C:Im⁡(z+1−3i1−3i)≥0}S_{2}=\left\{z \in C: \operatorname{Im}\left(\frac{z+1-\sqrt{3} i}{1-\sqrt{3} i}\right) \geq 0\right\} and S3={z∈C:Re⁡(z)≥0}\mathrm{S}_{3}=\{\mathrm{z} \in \mathrm{C}: \operatorname{Re}(\mathrm{z}) \geq 0\}.

Then

  1. Option A:

    125π6\frac{125 \pi}{6}

  2. Option B:

    125π24\frac{125 \pi}{24}

  3. Option C:

    125π4\frac{125 \pi}{4}

  4. Option D:

    125π12\frac{125 \pi}{12}

    Correct

Answer: D

Step-by-step solution

S1:x2+y2≤25\mathrm{S}_{1}: \mathrm{x}^{2}+\mathrm{y}^{2} \leq 25

S2:Im⁡S_{2}: \operatorname{Im} of z+(1−3i)(1−3i)≥0\frac{z+(1-\sqrt{3} i)}{(1-\sqrt{3} i)} \geq 0

Im⁡\operatorname{Im} of (x+iy1−3i+1)≥0\left(\frac{x+i y}{1-\sqrt{3} i}+1\right) \geq 0

Im⁡\operatorname{Im} of ((x+iy)(1+3i)4)≥0\left(\frac{(x+i y)(1+\sqrt{3} i)}{4}\right) \geq 0

⇒3x+y≥0\Rightarrow \sqrt{3} x+y \geq 0

S3:x≥0\mathrm{S}_{3}: \mathrm{x} \geq 0

Area =512(π(5)2)=\frac{5}{12}\left(\pi(5)^{2}\right)

Solution figure

Answer key and solution verified before publishing.

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Exam
JEE Main 2024
Subject
Mathematics
Chapter
Complex Numbers
Topic
Properties of Complex Numbers
Let S 1 =\ z in C: z leq 5\ , S 2 = \ z in C: Im (frac z+1-√(3) i… | JEE Main 2024 PYQ with Solution · DhiX AI