Mathematics · 3D Geometry

JEE Main 2024 — 5 April, Shift 2 — Question 9

Let (α,β,γ)(\alpha, \beta, \gamma) be the image of point (8,5,7)(8,5,7) in the line x−12=y+13=z−25\frac{x-1}{2}=\frac{y+1}{3}=\frac{z-2}{5}. Then α+β+γ\alpha+\beta+\gamma is equal to

  1. Option A:

    16

  2. Option B:

    18

  3. Option C:

    14

    Correct
  4. Option D:

    20

Answer: C

Step-by-step solution

AM→⋅(2i^+3j^+5k^)=0\overrightarrow{A M} \cdot(2 \hat{i}+3 \hat{j}+5 \hat{k})=0

(2λ−7)(2)+(3λ−6)(3)+(5λ−5)(5)=0(2 \lambda-7)(2)+(3 \lambda-6)(3)+(5 \lambda-5)(5)=0

38λ=5738 \lambda=57

λ=32\lambda=\frac{3}{2}

M(4,72,192)\mathrm{M}\left(4, \frac{7}{2}, \frac{19}{2}\right)

A′(0,2,12)\mathrm{A}^{\prime}(0,2,12)

Solution figure

Answer key and solution verified before publishing.

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Exam
JEE Main 2024
Subject
Mathematics
Chapter
3D Geometry
Topic
Vector & Cartesian forms of lines and planes
Let (α, β, γ) be the image of point (8,5,7) in the line… | JEE Main 2024 PYQ with Solution · DhiX AI