Find ā · b̄ if ā = 2î + 3ĵ and b̄ = î - 2ĵ:
A2
B0
C8
D-4
Answer & Solution
Correct answer: D. -4
ā · b̄ = (2)(1) + (3)(-2) = 2 - 6 = -4.
Related questions
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