Class 12 Vector Algebra · Assertion Reason1 Marksdot_product
Class 12 Maths · Vector Algebra · Assertion Reason #31
Assertion (A): If a = (3,−1,2) and b = (2,3,3), then a · b = 9.
Reason (R): The magnitude of (a₁,a₂,a₃) is √(a₁²+a₂²+a₃²).
✅ Step-by-Step Solution
Final Answer: Option (B): Both A and R are true, but R does not correctly explain A.
- The dot product is 6 − 3 + 6 = 9. The norm formula is true but does not explain the dot-product calculation.
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