Metamath Proof Explorer


Theorem maxidln0

Description: A ring with a maximal ideal is not the zero ring. (Contributed by Jeff Madsen, 17-Jun-2011)

Ref Expression
Hypotheses maxidln0.1 G = 1 st R
maxidln0.2 H = 2 nd R
maxidln0.3 Z = GId G
maxidln0.4 U = GId H
Assertion maxidln0 R RingOps M MaxIdl R U Z

Proof

Step Hyp Ref Expression
1 maxidln0.1 G = 1 st R
2 maxidln0.2 H = 2 nd R
3 maxidln0.3 Z = GId G
4 maxidln0.4 U = GId H
5 maxidlidl R RingOps M MaxIdl R M Idl R
6 1 3 idl0cl R RingOps M Idl R Z M
7 5 6 syldan R RingOps M MaxIdl R Z M
8 2 4 maxidln1 R RingOps M MaxIdl R ¬ U M
9 nelneq Z M ¬ U M ¬ Z = U
10 7 8 9 syl2anc R RingOps M MaxIdl R ¬ Z = U
11 10 neqned R RingOps M MaxIdl R Z U
12 11 necomd R RingOps M MaxIdl R U Z