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## 'Nine Eigen' printed from http://nrich.maths.org/

A vector ${\bf v}$ is fixed by a matrix if

$$

M{\bf v} = {\bf v}

$$

The vector direction of ${\bf v}$ is fixed if there is some number
$\lambda\neq 0$ such that

$$ M{\bf v} = \lambda{\bf v} $$

This resource introduces concepts
which appear in the later Further Pure Mathematics A
Level modules.