Metamath Proof Explorer


Theorem maxidln0

Description: Obsolete theorem, use mxidlnzr instead. A ring with a maximal ideal is not the zero ring. (Contributed by Jeff Madsen, 17-Jun-2011) (Proof modification is discouraged.) (New usage is discouraged.)

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