alleryAngle between two vectors ā = 2î + 2ĵ and b̄ = 4î - 4ĵ:
A180°
B90°
C45°
D0°
Answer & Solution
Correct answer: B. 90°
ā · b̄ = (2)(4) + (2)(-4) = 8 - 8 = 0. Hence vectors are PERPENDICULAR — angle 90°.
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