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Let the line of the shortest distance between the lines L_1: =( i+2 j+3 k)+λ ( i- j+ k) and L_2: =(4 i+5 j+6 k)+μ ( i+ j- k) intersect L_1 and L_2 at…

JEE Main 2024 — Mathematics Vectors & 3D Geometry

2024integermedium

Let the line of the shortest distance between the lines L1:r⃗=(i^+2j^+3k^)+λ(i^−j^+k^){L}_{1}:\vec{r}=(\hat{i}+2\hat{j}+3\hat{k})+\lambda (\hat{i}-\hat{j}+\hat{k})L1​:r=(i^+2j^​+3k^)+λ(i^−j^​+k^) and L2:r⃗=(4i^+5j^+6k^)+μ(i^+j^−k^){L}_{2}:\vec{r}=(4\hat{i}+5\hat{j}+6\hat{k})+\mu (\hat{i}+\hat{j}-\hat{k})L2​:r=(4i^+5j^​+6k^)+μ(i^+j^​−k^) intersect L1{L}_{1}L1​ and L2{L}_{2}L2​ at PPP and QQQ respectively. If (α,β,γ)(\alpha ,\beta ,\gamma )(α,β,γ) is the midpoint of the line segment PQPQPQ, then 2(α+β+γ)2(\alpha +\beta +\gamma )2(α+β+γ) is equal to___________

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Held on 1 Feb 2024 · Verified 6 Jul 2026.

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