Class 12 Three Dimensional Geometry · Short Answer2 Marksdirection_cosines
Class 12 Maths · Three Dimensional Geometry · Short Answer #76
Find direction cosines of the line through (−2,4,−5),(1,2,3).
✅ Step-by-Step Solution
Final Answer: ±(3,−2,8)/√77.
- Subtract endpoints to obtain d=(3,−2,8).
- Its norm is √(9+4+64)=√77.
- Normalize to obtain ±(3,−2,8)/√77.
📋 CBSE Stepwise Marking Scheme
- [0.5 marks] Subtract endpoints to obtain d=(3,−2,8).
- [1 mark] Its norm is √(9+4+64)=√77.
- [0.5 marks] Normalize to obtain ±(3,−2,8)/√77.
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