Chapter 2: Problem 54
What does \(M\) being free on \(m_{1}, \ldots, m_{n}\) say in terms of the elements of \(M\) ?
Short Answer
Step by step solution
Key Concepts
These are the key concepts you need to understand to accurately answer the question.
/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none}
Learning Materials
Features
Discover
Chapter 2: Problem 54
What does \(M\) being free on \(m_{1}, \ldots, m_{n}\) say in terms of the elements of \(M\) ?
These are the key concepts you need to understand to accurately answer the question.
All the tools & learning materials you need for study success - in one app.
Get started for free
Verify that for any \(R\)-module homomorphism \(\varphi: M \rightarrow M^{\prime}, \operatorname{Ker}(\varphi)\) and \(\operatorname{Im}(\varphi)\) are submodules of \(M\) and \(M^{\prime}\) respectively. Show that $$ 0 \longrightarrow \operatorname{Ker}(\varphi) \longrightarrow M \stackrel{\varphi}{\longrightarrow} \operatorname{Im}(\varphi) \longrightarrow 0 $$ is exact.
What are the additive and multiplicative identities in \(\prod R_{i}\) ? Is the map from \(R_{i}\) to \(\Pi R_{j}\) taking \(a_{i}\) to \(\left(0, \ldots, a_{i}, \ldots, 0\right.\) ) a ring homomorphism?
Factor \(Y^{3}-2 X Y^{2}+2 X^{2} Y+X^{3}\) into linear factors in \(\mathbb{C}[X, Y]\)
Let \(T: \mathbb{A}^{n} \rightarrow \mathbb{A}^{n}\) be an affine change of coordinates, \(T(P)=Q\). Show that \(\tilde{T}: \mathscr{O}_{Q}\left(\mathbb{A}^{n}\right) \rightarrow \mathscr{O}_{P}\left(\mathbb{A}^{n}\right)\) is an isomorphism. Show that \(\tilde{T}\) induces an isomorphism from \(\mathscr{O}_{Q}(V)\) to \(\mathscr{O}_{P}\left(V^{T}\right)\) if \(P \in V^{T}\), for \(V\) a subvariety of \(\mathbb{A}^{n}\).
Let \(F\) be an irreducible polynomial in \(k[X, Y]\), and suppose \(F\) is monic in \(Y\) : \(F=Y^{n}+a_{1}(X) Y^{n-1}+\cdots\), with \(n>0 .\) Let \(V=V(F) \subset \mathbb{A}^{2}\). Show that the natural homomorphism from \(k[X]\) to \(\Gamma(V)=k[X, Y] /(F)\) is one-to-one, so that \(k[X]\) may be regarded as a subring of \(\Gamma(V)\); show that the residues \(\overline{1}, \bar{Y}, \ldots, \bar{Y}^{n-1}\) generate \(\Gamma(V)\) over \(k[X]\) as a module.
What do you think about this solution?
We value your feedback to improve our textbook solutions.