Question

Questions about $\text{ker }(\alpha) \xrightarrow{u_1} \text{ker }(\beta)\xrightarrow{v_1}\text{ker }(\gamma)$ in Snake Lemma.

score 40 · Answer 1 · 2026-04-14 23:48:35

40

Views

Questions about $\text{ker }(\alpha) \xrightarrow{u_1} \text{ker }(\beta)\xrightarrow{v_1}\text{ker }(\gamma)$ in Snake Lemma.

Published on 14 Apr 2026 - 23:48

score 117 · Answer 2 · 2026-04-15 21:41:59

117

Views

Notation questions about $A^{r-1}\to A^r, A^n\to M:(1,0,\ldots,0)\to x_1,\ldots,(0,\ldots,0,1)\to x_n$ in Proposition 1.55 concerning free module

Published on 15 Apr 2026 - 21:41

score 28 · Answer 3 · 2026-04-16 04:14:45

28

Views

Notaional question about the projection map $A^n\to M$ and short exact sequence $A^m\to A^n\to M\to 0.$

Published on 16 Apr 2026 - 4:14

score 50 · Answer 4 · 2026-04-15 11:55:25

50

Views

Question about the maps: $K\to F$ and $L\to F$ in proof of proposition 1.59 concerning finitely presented module.

Published on 15 Apr 2026 - 11:55

score 35 · Answer 5 · 2026-04-13 11:13:47

35

Views

Correcting the map that proves countability of $N.$

Published on 13 Apr 2026 - 11:13

score 90 · Answer 6 · 2026-04-28 16:37:23

90

Views

Proving universal property in Kähler differentials

Published on 28 Apr 2026 - 16:37

score 88 · Answer 7 · 2026-04-17 04:50:45

88

Views

Tensor-restriction of scalars adjunction property but with Ext

Published on 17 Apr 2026 - 4:50

score 58 · Answer 8 · 2026-04-13 17:33:00

58

Views

Isomorphic to external sum $\implies$ is internal direct sum

Published on 13 Apr 2026 - 17:33

score 74 · Answer 9 · 2026-04-14 05:40:57

74

Views

Computing the presentation of a morphism of a $k$-algebras

Published on 14 Apr 2026 - 5:40

score 125 · Answer 10 · 2026-04-15 18:28:30

125

Views

$M_1 \oplus M_2$ is projective $\iff M_1$ and $M_2$ are both projective

Published on 15 Apr 2026 - 18:28

score 40 · Answer 11 · 2026-04-16 07:32:16

40

Views

The R-module $P$ is projective (the functor Hom$_R(P, −)$ : R-Mod $\to$ Ab is exact) iff the lifting property holds

Published on 16 Apr 2026 - 7:32

score 78 · Answer 12 · 2026-04-12 04:55:36

78

Views

Isomorphic to external direct sum but internal direct sum not defined

Published on 12 Apr 2026 - 4:55

score 50 · Answer 13 · 2026-04-13 02:16:07

50

Views

Incorrect proof for $e$ idempotent $\Rightarrow$ $eA$ projective

Published on 13 Apr 2026 - 2:16

score 147 · Answer 14 · 2026-04-15 20:12:04

147

Views

If $M_1$ and $M_2$ are R-modules, $R$ commutative. Show that $M_1 \oplus M_2$ is flat $\iff M_1$ and $M_2$ are both flat

Published on 15 Apr 2026 - 20:12

score 119 · Answer 15 · 2026-04-14 15:00:17

119

Views

Why a nonzero finite abelian group is not projective?

Published on 14 Apr 2026 - 15:00

List Question

Questions about $\text{ker }(\alpha) \xrightarrow{u_1} \text{ker }(\beta)\xrightarrow{v_1}\text{ker }(\gamma)$ in Snake Lemma.

Notation questions about $A^{r-1}\to A^r, A^n\to M:(1,0,\ldots,0)\to x_1,\ldots,(0,\ldots,0,1)\to x_n$ in Proposition 1.55 concerning free module

Notaional question about the projection map $A^n\to M$ and short exact sequence $A^m\to A^n\to M\to 0.$

Question about the maps: $K\to F$ and $L\to F$ in proof of proposition 1.59 concerning finitely presented module.

Correcting the map that proves countability of $N.$

Proving universal property in Kähler differentials

Tensor-restriction of scalars adjunction property but with Ext

Isomorphic to external sum $\implies$ is internal direct sum

Computing the presentation of a morphism of a $k$-algebras

$M_1 \oplus M_2$ is projective $\iff M_1$ and $M_2$ are both projective

The R-module $P$ is projective (the functor Hom$_R(P, −)$ : R-Mod $\to$ Ab is exact) iff the lifting property holds

Isomorphic to external direct sum but internal direct sum not defined

Incorrect proof for $e$ idempotent $\Rightarrow$ $eA$ projective

If $M_1$ and $M_2$ are R-modules, $R$ commutative. Show that $M_1 \oplus M_2$ is flat $\iff M_1$ and $M_2$ are both flat

Why a nonzero finite abelian group is not projective?

Trending Questions

Popular # Hahtags

Popular Questions