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Define two vectors v and u in $\mathbb{R}^3$. I know the geometric meaning of the inner and cross product.

Is there a meaning to the matrix resulting from $\textbf{uv}^T$?

1 Answers1

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For any vector $x$, $$ uv^T(x) = (v \cdot x)u $$ That is, If $u$ and $v$ are unit vectors, $uv^T(x)$ is the component of $x$ in the $v$ direction, taken into the $u$ direction.

This interpretation makes for a neat understanding of singular value decomposition.

Ben Grossmann
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