Mathematics · Circles

JEE Main 2026 — 24 January, Morning Shift — Question 2

Let a circle of radius 4 pass through the origin O , the points A(−3a,0)\mathrm{A}(-\sqrt{3} \mathrm{a}, 0) and B(0,−2 b)\mathrm{B}(0,-\sqrt{2} \mathrm{~b}), where a and b are real parameters and ab≠0\mathrm{ab} \neq 0. Then the locus of the centroid of △OAB\triangle \mathrm{OAB} is a circle of radius :

  1. Option A:

    53\frac{5}{3}

  2. Option B:

    73\frac{7}{3}

  3. Option C:

    83\frac{8}{3}

    Correct
  4. Option D:

    113\frac{11}{3}

Answer: C

Step-by-step solution

AB=8\mathrm{AB}=8

3a2+2b2=643 a^{2}+2 b^{2}=64 Centroid G(h,k)\mathrm{G}(\mathrm{h}, \mathrm{k})

h=−3a3,k=−2 b3\mathrm{h}=-\frac{\sqrt{3} \mathrm{a}}{3}, \mathrm{k}=-\frac{\sqrt{2} \mathrm{~b}}{3}

a=−3 h, b=−32k\mathrm{a}=-\sqrt{3} \mathrm{~h}, \mathrm{~b}=\frac{-3}{\sqrt{2}} \mathrm{k}

9 h2+9k2=649 \mathrm{~h}^{2}+9 \mathrm{k}^{2}=64

x2+y2=649\mathrm{x}^{2}+\mathrm{y}^{2}=\frac{64}{9}

r=83\mathrm{r}=\frac{8}{3}

Solution figure

Answer key and solution verified before publishing.

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Exam
JEE Main 2026
Subject
Mathematics
Chapter
Circles
Topic
Introduction to Circles
Let a circle of radius 4 pass through the origin O , the points A… | JEE Main 2026 PYQ with Solution · DhiX AI