Is the projective direct summand of middle of an exact sequence is determined by others?

$\DeclareMathOperator{\mod}{\mathrm{mod}}$When I’m learning the $\textit{representation theory of Artin algebras}$ wrote by M. Aulander, I. Reiten and S.O. Small, I find two questions in chapter...

29 August 2023 805 0 View