CBSE Class 12 Mathematics 2026 Main Paper 65(B) · Q252 Markspoint_reflection
CBSE Class 12 Mathematics 2026 Main Paper 65(B) · Question 25 (Three Dimensional Geometry)
Find the reflection of (2,−1,5) in r=(11,−2,−8)+t(10,−4,−11).
✅ Step-by-Step Solution
Final Answer: (0,5,1).
- The projection parameter is ((P−a)·d)/(d·d)=−237/237=−1.
- Thus the foot is H=(1,2,3).
- The reflection is 2H−P=(0,5,1).
📋 CBSE Stepwise Marking Scheme
- [0.5 marks] The projection parameter is ((P−a)·d)/(d·d)=−237/237=−1.
- [1 mark] Thus the foot is H=(1,2,3).
- [0.5 marks] The reflection is 2H−P=(0,5,1).
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