alleryVectors ā = î + 2ĵ + 3k̂ and b̄ = 2î + 3ĵ + αk̂ are perpendicular. Find α:
A-8/3
B-2
C-1
D8/3
Answer & Solution
Correct answer: A. -8/3
We have ā · b̄ = 0 → 2 + 6 + 3α.
That is ā · b̄ = 0 → 8 + 3α.
That is ā · b̄ = 0 → α.
So ā · b̄ = -8/3.
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