If [ā b̄ c̄] = 5, find [2ā b̄ c̄]:
A25
B2.5
C5
D10
Answer & Solution
Correct answer: D. 10
Scalar triple product is LINEAR in each vector: [kā b̄ c̄] = k[ā b̄ c̄] = k × 5. So [2ā b̄ c̄] = 2 × 5 = 10.
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