Projection/Minimal polynomial/Exercise

Let ${}V\neq 0$ be a finite-dimensional ${}K$-vector space, and let

$\varphi \colon V\longrightarrow V$

denote a projection. Show that the minimal polynomial of ${}\varphi$ is either ${}X$, or ${}X-1$, or ${}X(X-1)$.

Create a solution