Metamath Proof Explorer


Theorem unitrrg

Description: Units are regular elements. (Contributed by Stefan O'Rear, 22-Mar-2015)

Ref Expression
Hypotheses unitrrg.e ⊢ E = RLReg ⁡ R
unitrrg.u ⊢ U = Unit ⁡ R
Assertion unitrrg ⊢ R ∈ Ring → U ⊆ E

Proof

Step Hyp Ref Expression
1 unitrrg.e ⊢ E = RLReg ⁡ R
2 unitrrg.u ⊢ U = Unit ⁡ R
3 eqid ⊢ Base R = Base R
4 3 2 unitcl ⊢ x ∈ U → x ∈ Base R
5 4 adantl ⊢ R ∈ Ring ∧ x ∈ U → x ∈ Base R
6 oveq2 ⊢ x ⋅ R y = 0 R → inv r ⁡ R ⁡ x ⋅ R x ⋅ R y = inv r ⁡ R ⁡ x ⋅ R 0 R
7 eqid ⊢ inv r ⁡ R = inv r ⁡ R
8 eqid ⊢ ⋅ R = ⋅ R
9 eqid ⊢ 1 R = 1 R
10 2 7 8 9 unitlinv ⊢ R ∈ Ring ∧ x ∈ U → inv r ⁡ R ⁡ x ⋅ R x = 1 R
11 10 adantr ⊢ R ∈ Ring ∧ x ∈ U ∧ y ∈ Base R → inv r ⁡ R ⁡ x ⋅ R x = 1 R
12 11 oveq1d ⊢ R ∈ Ring ∧ x ∈ U ∧ y ∈ Base R → inv r ⁡ R ⁡ x ⋅ R x ⋅ R y = 1 R ⋅ R y
13 simpll ⊢ R ∈ Ring ∧ x ∈ U ∧ y ∈ Base R → R ∈ Ring
14 2 7 3 ringinvcl ⊢ R ∈ Ring ∧ x ∈ U → inv r ⁡ R ⁡ x ∈ Base R
15 14 adantr ⊢ R ∈ Ring ∧ x ∈ U ∧ y ∈ Base R → inv r ⁡ R ⁡ x ∈ Base R
16 5 adantr ⊢ R ∈ Ring ∧ x ∈ U ∧ y ∈ Base R → x ∈ Base R
17 simpr ⊢ R ∈ Ring ∧ x ∈ U ∧ y ∈ Base R → y ∈ Base R
18 3 8 ringass ⊢ R ∈ Ring ∧ inv r ⁡ R ⁡ x ∈ Base R ∧ x ∈ Base R ∧ y ∈ Base R → inv r ⁡ R ⁡ x ⋅ R x ⋅ R y = inv r ⁡ R ⁡ x ⋅ R x ⋅ R y
19 13 15 16 17 18 syl13anc ⊢ R ∈ Ring ∧ x ∈ U ∧ y ∈ Base R → inv r ⁡ R ⁡ x ⋅ R x ⋅ R y = inv r ⁡ R ⁡ x ⋅ R x ⋅ R y
20 3 8 9 ringlidm ⊢ R ∈ Ring ∧ y ∈ Base R → 1 R ⋅ R y = y
21 20 adantlr ⊢ R ∈ Ring ∧ x ∈ U ∧ y ∈ Base R → 1 R ⋅ R y = y
22 12 19 21 3eqtr3d ⊢ R ∈ Ring ∧ x ∈ U ∧ y ∈ Base R → inv r ⁡ R ⁡ x ⋅ R x ⋅ R y = y
23 eqid ⊢ 0 R = 0 R
24 3 8 23 ringrz ⊢ R ∈ Ring ∧ inv r ⁡ R ⁡ x ∈ Base R → inv r ⁡ R ⁡ x ⋅ R 0 R = 0 R
25 13 15 24 syl2anc ⊢ R ∈ Ring ∧ x ∈ U ∧ y ∈ Base R → inv r ⁡ R ⁡ x ⋅ R 0 R = 0 R
26 22 25 eqeq12d ⊢ R ∈ Ring ∧ x ∈ U ∧ y ∈ Base R → inv r ⁡ R ⁡ x ⋅ R x ⋅ R y = inv r ⁡ R ⁡ x ⋅ R 0 R ↔ y = 0 R
27 6 26 imbitrid ⊢ R ∈ Ring ∧ x ∈ U ∧ y ∈ Base R → x ⋅ R y = 0 R → y = 0 R
28 27 ralrimiva ⊢ R ∈ Ring ∧ x ∈ U → ∀ y ∈ Base R x ⋅ R y = 0 R → y = 0 R
29 1 3 8 23 isrrg ⊢ x ∈ E ↔ x ∈ Base R ∧ ∀ y ∈ Base R x ⋅ R y = 0 R → y = 0 R
30 5 28 29 sylanbrc ⊢ R ∈ Ring ∧ x ∈ U → x ∈ E
31 30 ex ⊢ R ∈ Ring → x ∈ U → x ∈ E
32 31 ssrdv ⊢ R ∈ Ring → U ⊆ E