Class 12 Three Dimensional Geometry · Short Answer2 Marksangles_between_lines
Class 12 Maths · Three Dimensional Geometry · Short Answer #74
Find the acute angle between directions (3,2,6),(1,2,2).
✅ Step-by-Step Solution
Final Answer: cos⁻¹(19/21).
- Use cos θ=|d·e|/(|d||e|).
- The dot product is 19 and the norms are 7 and 3.
- θ=cos⁻¹(19/21).
📋 CBSE Stepwise Marking Scheme
- [0.5 marks] Use cos θ=|d·e|/(|d||e|).
- [1 mark] The dot product is 19 and the norms are 7 and 3.
- [0.5 marks] θ=cos⁻¹(19/21).
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