Class 12 Vector Algebra · Conceptual Answer1 Marksvector_identities
Class 12 Maths · Vector Algebra · Conceptual Answer #43
If |a| = 1/2, |b| = 4/√3 and |a × b| = 1/√3, find |a · b|.
✅ Step-by-Step Solution
Final Answer: 1.
- Lagrange’s identity gives (a · b)² = (1/4)(16/3) − 1/3 = 1. The absolute dot product is 1; the angle may be acute or obtuse.
- 1.
📋 CBSE Stepwise Marking Scheme
- [0.5 marks] Lagrange’s identity gives (a · b)² = (1/4)(16/3) − 1/3 = 1. The absolute dot product is 1; the angle may be acute or obtuse.
- [0.5 marks] 1.
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