Remark 13.19.5. Let $\mathcal{A}$ be an abelian category. Suppose that $\alpha : K^\bullet \to L^\bullet $ is a quasi-isomorphism of complexes. Let $P^\bullet $ be a bounded above complex of projectives. Then
\[ \mathop{\mathrm{Hom}}\nolimits _{K(\mathcal{A})}(P^\bullet , K^\bullet ) \longrightarrow \mathop{\mathrm{Hom}}\nolimits _{K(\mathcal{A})}(P^\bullet , L^\bullet ) \]
is an isomorphism. This is dual to Remark 13.18.5.
Comments (1)
Comment #9851 by hijyen belgesi on