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CBSE Class 12 Mathematics 2026 Supplementary Paper 65(B)/7 · Q121 Marksperpendicular_lines

CBSE Class 12 Mathematics 2026 Supplementary Paper 65(B)/7 · Question 12 (Three Dimensional Geometry)

Find λ if (x−3)/(3λ)=(y+2)/1=(3−z)/7 and (4−x)/3=(y−5)/(2λ)=(z−1)/2 are perpendicular.

✅ Step-by-Step Solution

Final Answer: −2
  1. Their directions (3λ,1,−7) and (−3,2λ,2) have dot product −7λ−14. Set it to zero.

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All Questions in CBSE Class 12 Mathematics 2026 Supplementary Paper 65(B)/7

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