Proof of Theorem unitnegcl
| Step | Hyp | Ref
 | Expression | 
| 1 |   | simpl 109 | 
. . 3
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → 𝑅 ∈ Ring) | 
| 2 |   | ringgrp 13557 | 
. . . . . 6
⊢ (𝑅 ∈ Ring → 𝑅 ∈ Grp) | 
| 3 |   | eqidd 2197 | 
. . . . . . 7
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → (Base‘𝑅) = (Base‘𝑅)) | 
| 4 |   | unitnegcl.1 | 
. . . . . . . 8
⊢ 𝑈 = (Unit‘𝑅) | 
| 5 | 4 | a1i 9 | 
. . . . . . 7
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → 𝑈 = (Unit‘𝑅)) | 
| 6 |   | ringsrg 13603 | 
. . . . . . . 8
⊢ (𝑅 ∈ Ring → 𝑅 ∈ SRing) | 
| 7 | 6 | adantr 276 | 
. . . . . . 7
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → 𝑅 ∈ SRing) | 
| 8 |   | simpr 110 | 
. . . . . . 7
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → 𝑋 ∈ 𝑈) | 
| 9 | 3, 5, 7, 8 | unitcld 13664 | 
. . . . . 6
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → 𝑋 ∈ (Base‘𝑅)) | 
| 10 |   | eqid 2196 | 
. . . . . . 7
⊢
(Base‘𝑅) =
(Base‘𝑅) | 
| 11 |   | unitnegcl.2 | 
. . . . . . 7
⊢ 𝑁 = (invg‘𝑅) | 
| 12 | 10, 11 | grpinvcl 13180 | 
. . . . . 6
⊢ ((𝑅 ∈ Grp ∧ 𝑋 ∈ (Base‘𝑅)) → (𝑁‘𝑋) ∈ (Base‘𝑅)) | 
| 13 | 2, 9, 12 | syl2an2r 595 | 
. . . . 5
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → (𝑁‘𝑋) ∈ (Base‘𝑅)) | 
| 14 |   | eqid 2196 | 
. . . . . 6
⊢
(∥r‘𝑅) = (∥r‘𝑅) | 
| 15 | 10, 14, 11 | dvdsrneg 13659 | 
. . . . 5
⊢ ((𝑅 ∈ Ring ∧ (𝑁‘𝑋) ∈ (Base‘𝑅)) → (𝑁‘𝑋)(∥r‘𝑅)(𝑁‘(𝑁‘𝑋))) | 
| 16 | 13, 15 | syldan 282 | 
. . . 4
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → (𝑁‘𝑋)(∥r‘𝑅)(𝑁‘(𝑁‘𝑋))) | 
| 17 | 10, 11 | grpinvinv 13199 | 
. . . . 5
⊢ ((𝑅 ∈ Grp ∧ 𝑋 ∈ (Base‘𝑅)) → (𝑁‘(𝑁‘𝑋)) = 𝑋) | 
| 18 | 2, 9, 17 | syl2an2r 595 | 
. . . 4
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → (𝑁‘(𝑁‘𝑋)) = 𝑋) | 
| 19 | 16, 18 | breqtrd 4059 | 
. . 3
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → (𝑁‘𝑋)(∥r‘𝑅)𝑋) | 
| 20 |   | eqidd 2197 | 
. . . . . 6
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → (1r‘𝑅) = (1r‘𝑅)) | 
| 21 |   | eqidd 2197 | 
. . . . . 6
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → (∥r‘𝑅) =
(∥r‘𝑅)) | 
| 22 |   | eqidd 2197 | 
. . . . . 6
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → (oppr‘𝑅) =
(oppr‘𝑅)) | 
| 23 |   | eqidd 2197 | 
. . . . . 6
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) →
(∥r‘(oppr‘𝑅)) =
(∥r‘(oppr‘𝑅))) | 
| 24 | 5, 20, 21, 22, 23, 7 | isunitd 13662 | 
. . . . 5
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → (𝑋 ∈ 𝑈 ↔ (𝑋(∥r‘𝑅)(1r‘𝑅) ∧ 𝑋(∥r‘(oppr‘𝑅))(1r‘𝑅)))) | 
| 25 | 8, 24 | mpbid 147 | 
. . . 4
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → (𝑋(∥r‘𝑅)(1r‘𝑅) ∧ 𝑋(∥r‘(oppr‘𝑅))(1r‘𝑅))) | 
| 26 | 25 | simpld 112 | 
. . 3
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → 𝑋(∥r‘𝑅)(1r‘𝑅)) | 
| 27 | 10, 14 | dvdsrtr 13657 | 
. . 3
⊢ ((𝑅 ∈ Ring ∧ (𝑁‘𝑋)(∥r‘𝑅)𝑋 ∧ 𝑋(∥r‘𝑅)(1r‘𝑅)) → (𝑁‘𝑋)(∥r‘𝑅)(1r‘𝑅)) | 
| 28 | 1, 19, 26, 27 | syl3anc 1249 | 
. 2
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → (𝑁‘𝑋)(∥r‘𝑅)(1r‘𝑅)) | 
| 29 |   | eqid 2196 | 
. . . . 5
⊢
(oppr‘𝑅) = (oppr‘𝑅) | 
| 30 | 29 | opprring 13635 | 
. . . 4
⊢ (𝑅 ∈ Ring →
(oppr‘𝑅) ∈ Ring) | 
| 31 | 30 | adantr 276 | 
. . 3
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → (oppr‘𝑅) ∈ Ring) | 
| 32 | 29, 10 | opprbasg 13631 | 
. . . . . . . . 9
⊢ (𝑅 ∈ Ring →
(Base‘𝑅) =
(Base‘(oppr‘𝑅))) | 
| 33 | 32 | eleq2d 2266 | 
. . . . . . . 8
⊢ (𝑅 ∈ Ring → ((𝑁‘𝑋) ∈ (Base‘𝑅) ↔ (𝑁‘𝑋) ∈
(Base‘(oppr‘𝑅)))) | 
| 34 | 33 | adantr 276 | 
. . . . . . 7
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → ((𝑁‘𝑋) ∈ (Base‘𝑅) ↔ (𝑁‘𝑋) ∈
(Base‘(oppr‘𝑅)))) | 
| 35 | 13, 34 | mpbid 147 | 
. . . . . 6
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → (𝑁‘𝑋) ∈
(Base‘(oppr‘𝑅))) | 
| 36 |   | eqid 2196 | 
. . . . . . 7
⊢
(Base‘(oppr‘𝑅)) =
(Base‘(oppr‘𝑅)) | 
| 37 |   | eqid 2196 | 
. . . . . . 7
⊢
(∥r‘(oppr‘𝑅)) =
(∥r‘(oppr‘𝑅)) | 
| 38 |   | eqid 2196 | 
. . . . . . 7
⊢
(invg‘(oppr‘𝑅)) =
(invg‘(oppr‘𝑅)) | 
| 39 | 36, 37, 38 | dvdsrneg 13659 | 
. . . . . 6
⊢
(((oppr‘𝑅) ∈ Ring ∧ (𝑁‘𝑋) ∈
(Base‘(oppr‘𝑅))) → (𝑁‘𝑋)(∥r‘(oppr‘𝑅))((invg‘(oppr‘𝑅))‘(𝑁‘𝑋))) | 
| 40 | 30, 35, 39 | syl2an2r 595 | 
. . . . 5
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → (𝑁‘𝑋)(∥r‘(oppr‘𝑅))((invg‘(oppr‘𝑅))‘(𝑁‘𝑋))) | 
| 41 | 29, 11 | opprnegg 13639 | 
. . . . . . . 8
⊢ (𝑅 ∈ Ring → 𝑁 =
(invg‘(oppr‘𝑅))) | 
| 42 | 41 | fveq1d 5560 | 
. . . . . . 7
⊢ (𝑅 ∈ Ring → (𝑁‘(𝑁‘𝑋)) =
((invg‘(oppr‘𝑅))‘(𝑁‘𝑋))) | 
| 43 | 42 | breq2d 4045 | 
. . . . . 6
⊢ (𝑅 ∈ Ring → ((𝑁‘𝑋)(∥r‘(oppr‘𝑅))(𝑁‘(𝑁‘𝑋))
↔ (𝑁‘𝑋)(∥r‘(oppr‘𝑅))((invg‘(oppr‘𝑅))‘(𝑁‘𝑋)))) | 
| 44 | 43 | adantr 276 | 
. . . . 5
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → ((𝑁‘𝑋)(∥r‘(oppr‘𝑅))(𝑁‘(𝑁‘𝑋))
↔ (𝑁‘𝑋)(∥r‘(oppr‘𝑅))((invg‘(oppr‘𝑅))‘(𝑁‘𝑋)))) | 
| 45 | 40, 44 | mpbird 167 | 
. . . 4
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → (𝑁‘𝑋)(∥r‘(oppr‘𝑅))(𝑁‘(𝑁‘𝑋))) | 
| 46 | 45, 18 | breqtrd 4059 | 
. . 3
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → (𝑁‘𝑋)(∥r‘(oppr‘𝑅))𝑋) | 
| 47 | 25 | simprd 114 | 
. . 3
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → 𝑋(∥r‘(oppr‘𝑅))(1r‘𝑅)) | 
| 48 | 36, 37 | dvdsrtr 13657 | 
. . 3
⊢
(((oppr‘𝑅) ∈ Ring ∧ (𝑁‘𝑋)(∥r‘(oppr‘𝑅))𝑋 ∧ 𝑋(∥r‘(oppr‘𝑅))(1r‘𝑅)) → (𝑁‘𝑋)(∥r‘(oppr‘𝑅))(1r‘𝑅)) | 
| 49 | 31, 46, 47, 48 | syl3anc 1249 | 
. 2
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → (𝑁‘𝑋)(∥r‘(oppr‘𝑅))(1r‘𝑅)) | 
| 50 | 5, 20, 21, 22, 23, 7 | isunitd 13662 | 
. 2
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → ((𝑁‘𝑋) ∈ 𝑈 ↔ ((𝑁‘𝑋)(∥r‘𝑅)(1r‘𝑅) ∧ (𝑁‘𝑋)(∥r‘(oppr‘𝑅))(1r‘𝑅)))) | 
| 51 | 28, 49, 50 | mpbir2and 946 | 
1
⊢ ((𝑅 ∈ Ring ∧ 𝑋 ∈ 𝑈) → (𝑁‘𝑋) ∈ 𝑈) |