Lemma 22.20.10. In Situation 22.20.2 let $f: x \to y$ be a morphism in $\text{Comp}(\mathcal{A})$. The triangle $(y, c(f), x[1], i, p, f[1])$ is the triangle associated to the admissible short exact sequence

$\xymatrix{y\ar[r] & c(f) \ar[r] & x[1]}$

where the cone $c(f)$ is defined as in Lemma 22.20.1.

Proof. This follows from axiom (C). $\square$

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