The scalar (dot) product $\vec{a}\cdot\vec{b}$ equals:
A$|\vec a||\vec b|\tan\theta$
B$|\vec a||\vec b|\cos\theta$
C$|\vec a|+|\vec b|$
D$|\vec a||\vec b|\sin\theta$
Answer & Solution
Correct answer: B. $|\vec a||\vec b|\cos\theta$
The scalar product is â·b̂ = |a||b|cosθ.
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