alleryFor ā = 2î + 3ĵ and b̄ = αî + 6ĵ to be parallel, α equals:
A4
B6
C3
D12
Answer & Solution
Correct answer: A. 4
**For parallel:** components must be proportional.
α/2 = 6/3 → α/2 = 2 → α = 4. (Check: b̄ = 4î + 6ĵ = 2(2î + 3ĵ) = 2ā ✓.)
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