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There does indeed exist a notion of multiplying two vectors together, though it's slightly different from the multiplication that we're used to seeing.

The dot product (or scalar product) of two vectors v\vec{v} and w\vec{w} is defined as:

vw=vwcosθ\vec{v} \cdot \vec{w} = |\vec{v}| |\vec{w}| \cos\theta

where θ\theta is the angle (in degrees or radians) made between the two vectors when both of their "tails" are placed at the origin, i.e.

Dot product

You might be asking yourself: why is this seemingly arbitrary definition a notion of multiplication?

Why not multiply the two vectors component by component, similar to how addition, subtraction, and scal

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... continued in the full lesson.

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