Metamath Proof Explorer


Theorem recexsrlem

Description: The reciprocal of a positive signed real exists. Part of Proposition 9-4.3 of Gleason p. 126. (Contributed by NM, 15-May-1996) (New usage is discouraged.)

Ref Expression
Assertion recexsrlem ⊢ 0 𝑹 < 𝑹 A → ∃ x ∈ 𝑹 A ⋅ 𝑹 x = 1 𝑹

Proof

Step Hyp Ref Expression
1 ltrelsr ⊢ < 𝑹 ⊆ 𝑹 × 𝑹
2 1 brel ⊢ 0 𝑹 < 𝑹 A → 0 𝑹 ∈ 𝑹 ∧ A ∈ 𝑹
3 2 simprd ⊢ 0 𝑹 < 𝑹 A → A ∈ 𝑹
4 df-nr ⊢ 𝑹 = 𝑷 × 𝑷 / ~ 𝑹
5 breq2 ⊢ y z ~ 𝑹 = A → 0 𝑹 < 𝑹 y z ~ 𝑹 ↔ 0 𝑹 < 𝑹 A
6 oveq1 ⊢ y z ~ 𝑹 = A → y z ~ 𝑹 ⋅ 𝑹 x = A ⋅ 𝑹 x
7 6 eqeq1d ⊢ y z ~ 𝑹 = A → y z ~ 𝑹 ⋅ 𝑹 x = 1 𝑹 ↔ A ⋅ 𝑹 x = 1 𝑹
8 7 rexbidv ⊢ y z ~ 𝑹 = A → ∃ x ∈ 𝑹 y z ~ 𝑹 ⋅ 𝑹 x = 1 𝑹 ↔ ∃ x ∈ 𝑹 A ⋅ 𝑹 x = 1 𝑹
9 5 8 imbi12d ⊢ y z ~ 𝑹 = A → 0 𝑹 < 𝑹 y z ~ 𝑹 → ∃ x ∈ 𝑹 y z ~ 𝑹 ⋅ 𝑹 x = 1 𝑹 ↔ 0 𝑹 < 𝑹 A → ∃ x ∈ 𝑹 A ⋅ 𝑹 x = 1 𝑹
10 gt0srpr ⊢ 0 𝑹 < 𝑹 y z ~ 𝑹 ↔ z < 𝑷 y
11 ltexpri ⊢ z < 𝑷 y → ∃ w ∈ 𝑷 z + 𝑷 w = y
12 10 11 sylbi ⊢ 0 𝑹 < 𝑹 y z ~ 𝑹 → ∃ w ∈ 𝑷 z + 𝑷 w = y
13 recexpr ⊢ w ∈ 𝑷 → ∃ v ∈ 𝑷 w ⋅ 𝑷 v = 1 𝑷
14 1pr ⊢ 1 𝑷 ∈ 𝑷
15 addclpr ⊢ v ∈ 𝑷 ∧ 1 𝑷 ∈ 𝑷 → v + 𝑷 1 𝑷 ∈ 𝑷
16 14 15 mpan2 ⊢ v ∈ 𝑷 → v + 𝑷 1 𝑷 ∈ 𝑷
17 enrex ⊢ ~ 𝑹 ∈ V
18 17 4 ecopqsi ⊢ v + 𝑷 1 𝑷 ∈ 𝑷 ∧ 1 𝑷 ∈ 𝑷 → v + 𝑷 1 𝑷 1 𝑷 ~ 𝑹 ∈ 𝑹
19 16 14 18 sylancl ⊢ v ∈ 𝑷 → v + 𝑷 1 𝑷 1 𝑷 ~ 𝑹 ∈ 𝑹
20 19 ad2antlr ⊢ y ∈ 𝑷 ∧ z ∈ 𝑷 ∧ v ∈ 𝑷 ∧ w ⋅ 𝑷 v = 1 𝑷 ∧ z + 𝑷 w = y → v + 𝑷 1 𝑷 1 𝑷 ~ 𝑹 ∈ 𝑹
21 16 14 jctir ⊢ v ∈ 𝑷 → v + 𝑷 1 𝑷 ∈ 𝑷 ∧ 1 𝑷 ∈ 𝑷
22 21 anim2i ⊢ y ∈ 𝑷 ∧ z ∈ 𝑷 ∧ v ∈ 𝑷 → y ∈ 𝑷 ∧ z ∈ 𝑷 ∧ v + 𝑷 1 𝑷 ∈ 𝑷 ∧ 1 𝑷 ∈ 𝑷
23 22 adantr ⊢ y ∈ 𝑷 ∧ z ∈ 𝑷 ∧ v ∈ 𝑷 ∧ w ⋅ 𝑷 v = 1 𝑷 ∧ z + 𝑷 w = y → y ∈ 𝑷 ∧ z ∈ 𝑷 ∧ v + 𝑷 1 𝑷 ∈ 𝑷 ∧ 1 𝑷 ∈ 𝑷
24 mulsrpr ⊢ y ∈ 𝑷 ∧ z ∈ 𝑷 ∧ v + 𝑷 1 𝑷 ∈ 𝑷 ∧ 1 𝑷 ∈ 𝑷 → y z ~ 𝑹 ⋅ 𝑹 v + 𝑷 1 𝑷 1 𝑷 ~ 𝑹 = y ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 v + 𝑷 1 𝑷 ~ 𝑹
25 23 24 syl ⊢ y ∈ 𝑷 ∧ z ∈ 𝑷 ∧ v ∈ 𝑷 ∧ w ⋅ 𝑷 v = 1 𝑷 ∧ z + 𝑷 w = y → y z ~ 𝑹 ⋅ 𝑹 v + 𝑷 1 𝑷 1 𝑷 ~ 𝑹 = y ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 v + 𝑷 1 𝑷 ~ 𝑹
26 oveq1 ⊢ z + 𝑷 w = y → z + 𝑷 w ⋅ 𝑷 v = y ⋅ 𝑷 v
27 26 eqcomd ⊢ z + 𝑷 w = y → y ⋅ 𝑷 v = z + 𝑷 w ⋅ 𝑷 v
28 vex ⊢ z ∈ V
29 vex ⊢ w ∈ V
30 vex ⊢ v ∈ V
31 mulcompr ⊢ u ⋅ 𝑷 f = f ⋅ 𝑷 u
32 distrpr ⊢ u ⋅ 𝑷 f + 𝑷 x = u ⋅ 𝑷 f + 𝑷 u ⋅ 𝑷 x
33 28 29 30 31 32 caovdir ⊢ z + 𝑷 w ⋅ 𝑷 v = z ⋅ 𝑷 v + 𝑷 w ⋅ 𝑷 v
34 oveq2 ⊢ w ⋅ 𝑷 v = 1 𝑷 → z ⋅ 𝑷 v + 𝑷 w ⋅ 𝑷 v = z ⋅ 𝑷 v + 𝑷 1 𝑷
35 33 34 eqtrid ⊢ w ⋅ 𝑷 v = 1 𝑷 → z + 𝑷 w ⋅ 𝑷 v = z ⋅ 𝑷 v + 𝑷 1 𝑷
36 27 35 sylan9eqr ⊢ w ⋅ 𝑷 v = 1 𝑷 ∧ z + 𝑷 w = y → y ⋅ 𝑷 v = z ⋅ 𝑷 v + 𝑷 1 𝑷
37 36 oveq1d ⊢ w ⋅ 𝑷 v = 1 𝑷 ∧ z + 𝑷 w = y → y ⋅ 𝑷 v + 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 = z ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷
38 ovex ⊢ z ⋅ 𝑷 v ∈ V
39 14 elexi ⊢ 1 𝑷 ∈ V
40 ovex ⊢ y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 ∈ V
41 addcompr ⊢ u + 𝑷 f = f + 𝑷 u
42 addasspr ⊢ u + 𝑷 f + 𝑷 x = u + 𝑷 f + 𝑷 x
43 38 39 40 41 42 caov32 ⊢ z ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 = z ⋅ 𝑷 v + 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 + 𝑷 1 𝑷
44 37 43 eqtrdi ⊢ w ⋅ 𝑷 v = 1 𝑷 ∧ z + 𝑷 w = y → y ⋅ 𝑷 v + 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 = z ⋅ 𝑷 v + 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 + 𝑷 1 𝑷
45 44 oveq1d ⊢ w ⋅ 𝑷 v = 1 𝑷 ∧ z + 𝑷 w = y → y ⋅ 𝑷 v + 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 + 𝑷 1 𝑷 = z ⋅ 𝑷 v + 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷
46 addasspr ⊢ z ⋅ 𝑷 v + 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 = z ⋅ 𝑷 v + 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷
47 45 46 eqtrdi ⊢ w ⋅ 𝑷 v = 1 𝑷 ∧ z + 𝑷 w = y → y ⋅ 𝑷 v + 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 + 𝑷 1 𝑷 = z ⋅ 𝑷 v + 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷
48 distrpr ⊢ y ⋅ 𝑷 v + 𝑷 1 𝑷 = y ⋅ 𝑷 v + 𝑷 y ⋅ 𝑷 1 𝑷
49 48 oveq1i ⊢ y ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 = y ⋅ 𝑷 v + 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷
50 addasspr ⊢ y ⋅ 𝑷 v + 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 = y ⋅ 𝑷 v + 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷
51 49 50 eqtri ⊢ y ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 = y ⋅ 𝑷 v + 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷
52 51 oveq1i ⊢ y ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 + 𝑷 1 𝑷 = y ⋅ 𝑷 v + 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 + 𝑷 1 𝑷
53 distrpr ⊢ z ⋅ 𝑷 v + 𝑷 1 𝑷 = z ⋅ 𝑷 v + 𝑷 z ⋅ 𝑷 1 𝑷
54 53 oveq2i ⊢ y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 v + 𝑷 1 𝑷 = y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 v + 𝑷 z ⋅ 𝑷 1 𝑷
55 ovex ⊢ y ⋅ 𝑷 1 𝑷 ∈ V
56 ovex ⊢ z ⋅ 𝑷 1 𝑷 ∈ V
57 55 38 56 41 42 caov12 ⊢ y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 v + 𝑷 z ⋅ 𝑷 1 𝑷 = z ⋅ 𝑷 v + 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷
58 54 57 eqtri ⊢ y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 v + 𝑷 1 𝑷 = z ⋅ 𝑷 v + 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷
59 58 oveq1i ⊢ y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷 = z ⋅ 𝑷 v + 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷
60 47 52 59 3eqtr4g ⊢ w ⋅ 𝑷 v = 1 𝑷 ∧ z + 𝑷 w = y → y ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 + 𝑷 1 𝑷 = y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷
61 mulclpr ⊢ y ∈ 𝑷 ∧ v + 𝑷 1 𝑷 ∈ 𝑷 → y ⋅ 𝑷 v + 𝑷 1 𝑷 ∈ 𝑷
62 16 61 sylan2 ⊢ y ∈ 𝑷 ∧ v ∈ 𝑷 → y ⋅ 𝑷 v + 𝑷 1 𝑷 ∈ 𝑷
63 mulclpr ⊢ z ∈ 𝑷 ∧ 1 𝑷 ∈ 𝑷 → z ⋅ 𝑷 1 𝑷 ∈ 𝑷
64 14 63 mpan2 ⊢ z ∈ 𝑷 → z ⋅ 𝑷 1 𝑷 ∈ 𝑷
65 addclpr ⊢ y ⋅ 𝑷 v + 𝑷 1 𝑷 ∈ 𝑷 ∧ z ⋅ 𝑷 1 𝑷 ∈ 𝑷 → y ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 ∈ 𝑷
66 62 64 65 syl2an ⊢ y ∈ 𝑷 ∧ v ∈ 𝑷 ∧ z ∈ 𝑷 → y ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 ∈ 𝑷
67 66 an32s ⊢ y ∈ 𝑷 ∧ z ∈ 𝑷 ∧ v ∈ 𝑷 → y ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 ∈ 𝑷
68 mulclpr ⊢ y ∈ 𝑷 ∧ 1 𝑷 ∈ 𝑷 → y ⋅ 𝑷 1 𝑷 ∈ 𝑷
69 14 68 mpan2 ⊢ y ∈ 𝑷 → y ⋅ 𝑷 1 𝑷 ∈ 𝑷
70 mulclpr ⊢ z ∈ 𝑷 ∧ v + 𝑷 1 𝑷 ∈ 𝑷 → z ⋅ 𝑷 v + 𝑷 1 𝑷 ∈ 𝑷
71 16 70 sylan2 ⊢ z ∈ 𝑷 ∧ v ∈ 𝑷 → z ⋅ 𝑷 v + 𝑷 1 𝑷 ∈ 𝑷
72 addclpr ⊢ y ⋅ 𝑷 1 𝑷 ∈ 𝑷 ∧ z ⋅ 𝑷 v + 𝑷 1 𝑷 ∈ 𝑷 → y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 v + 𝑷 1 𝑷 ∈ 𝑷
73 69 71 72 syl2an ⊢ y ∈ 𝑷 ∧ z ∈ 𝑷 ∧ v ∈ 𝑷 → y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 v + 𝑷 1 𝑷 ∈ 𝑷
74 73 anassrs ⊢ y ∈ 𝑷 ∧ z ∈ 𝑷 ∧ v ∈ 𝑷 → y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 v + 𝑷 1 𝑷 ∈ 𝑷
75 67 74 jca ⊢ y ∈ 𝑷 ∧ z ∈ 𝑷 ∧ v ∈ 𝑷 → y ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 ∈ 𝑷 ∧ y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 v + 𝑷 1 𝑷 ∈ 𝑷
76 addclpr ⊢ 1 𝑷 ∈ 𝑷 ∧ 1 𝑷 ∈ 𝑷 → 1 𝑷 + 𝑷 1 𝑷 ∈ 𝑷
77 14 14 76 mp2an ⊢ 1 𝑷 + 𝑷 1 𝑷 ∈ 𝑷
78 77 14 pm3.2i ⊢ 1 𝑷 + 𝑷 1 𝑷 ∈ 𝑷 ∧ 1 𝑷 ∈ 𝑷
79 enreceq ⊢ y ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 ∈ 𝑷 ∧ y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 v + 𝑷 1 𝑷 ∈ 𝑷 ∧ 1 𝑷 + 𝑷 1 𝑷 ∈ 𝑷 ∧ 1 𝑷 ∈ 𝑷 → y ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 v + 𝑷 1 𝑷 ~ 𝑹 = 1 𝑷 + 𝑷 1 𝑷 1 𝑷 ~ 𝑹 ↔ y ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 + 𝑷 1 𝑷 = y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷
80 75 78 79 sylancl ⊢ y ∈ 𝑷 ∧ z ∈ 𝑷 ∧ v ∈ 𝑷 → y ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 v + 𝑷 1 𝑷 ~ 𝑹 = 1 𝑷 + 𝑷 1 𝑷 1 𝑷 ~ 𝑹 ↔ y ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 + 𝑷 1 𝑷 = y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 1 𝑷 + 𝑷 1 𝑷
81 60 80 imbitrrid ⊢ y ∈ 𝑷 ∧ z ∈ 𝑷 ∧ v ∈ 𝑷 → w ⋅ 𝑷 v = 1 𝑷 ∧ z + 𝑷 w = y → y ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 v + 𝑷 1 𝑷 ~ 𝑹 = 1 𝑷 + 𝑷 1 𝑷 1 𝑷 ~ 𝑹
82 81 imp ⊢ y ∈ 𝑷 ∧ z ∈ 𝑷 ∧ v ∈ 𝑷 ∧ w ⋅ 𝑷 v = 1 𝑷 ∧ z + 𝑷 w = y → y ⋅ 𝑷 v + 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 1 𝑷 y ⋅ 𝑷 1 𝑷 + 𝑷 z ⋅ 𝑷 v + 𝑷 1 𝑷 ~ 𝑹 = 1 𝑷 + 𝑷 1 𝑷 1 𝑷 ~ 𝑹
83 25 82 eqtrd ⊢ y ∈ 𝑷 ∧ z ∈ 𝑷 ∧ v ∈ 𝑷 ∧ w ⋅ 𝑷 v = 1 𝑷 ∧ z + 𝑷 w = y → y z ~ 𝑹 ⋅ 𝑹 v + 𝑷 1 𝑷 1 𝑷 ~ 𝑹 = 1 𝑷 + 𝑷 1 𝑷 1 𝑷 ~ 𝑹
84 df-1r ⊢ 1 𝑹 = 1 𝑷 + 𝑷 1 𝑷 1 𝑷 ~ 𝑹
85 83 84 eqtr4di ⊢ y ∈ 𝑷 ∧ z ∈ 𝑷 ∧ v ∈ 𝑷 ∧ w ⋅ 𝑷 v = 1 𝑷 ∧ z + 𝑷 w = y → y z ~ 𝑹 ⋅ 𝑹 v + 𝑷 1 𝑷 1 𝑷 ~ 𝑹 = 1 𝑹
86 oveq2 ⊢ x = v + 𝑷 1 𝑷 1 𝑷 ~ 𝑹 → y z ~ 𝑹 ⋅ 𝑹 x = y z ~ 𝑹 ⋅ 𝑹 v + 𝑷 1 𝑷 1 𝑷 ~ 𝑹
87 86 eqeq1d ⊢ x = v + 𝑷 1 𝑷 1 𝑷 ~ 𝑹 → y z ~ 𝑹 ⋅ 𝑹 x = 1 𝑹 ↔ y z ~ 𝑹 ⋅ 𝑹 v + 𝑷 1 𝑷 1 𝑷 ~ 𝑹 = 1 𝑹
88 87 rspcev ⊢ v + 𝑷 1 𝑷 1 𝑷 ~ 𝑹 ∈ 𝑹 ∧ y z ~ 𝑹 ⋅ 𝑹 v + 𝑷 1 𝑷 1 𝑷 ~ 𝑹 = 1 𝑹 → ∃ x ∈ 𝑹 y z ~ 𝑹 ⋅ 𝑹 x = 1 𝑹
89 20 85 88 syl2anc ⊢ y ∈ 𝑷 ∧ z ∈ 𝑷 ∧ v ∈ 𝑷 ∧ w ⋅ 𝑷 v = 1 𝑷 ∧ z + 𝑷 w = y → ∃ x ∈ 𝑹 y z ~ 𝑹 ⋅ 𝑹 x = 1 𝑹
90 89 exp43 ⊢ y ∈ 𝑷 ∧ z ∈ 𝑷 → v ∈ 𝑷 → w ⋅ 𝑷 v = 1 𝑷 → z + 𝑷 w = y → ∃ x ∈ 𝑹 y z ~ 𝑹 ⋅ 𝑹 x = 1 𝑹
91 90 rexlimdv ⊢ y ∈ 𝑷 ∧ z ∈ 𝑷 → ∃ v ∈ 𝑷 w ⋅ 𝑷 v = 1 𝑷 → z + 𝑷 w = y → ∃ x ∈ 𝑹 y z ~ 𝑹 ⋅ 𝑹 x = 1 𝑹
92 13 91 syl5 ⊢ y ∈ 𝑷 ∧ z ∈ 𝑷 → w ∈ 𝑷 → z + 𝑷 w = y → ∃ x ∈ 𝑹 y z ~ 𝑹 ⋅ 𝑹 x = 1 𝑹
93 92 rexlimdv ⊢ y ∈ 𝑷 ∧ z ∈ 𝑷 → ∃ w ∈ 𝑷 z + 𝑷 w = y → ∃ x ∈ 𝑹 y z ~ 𝑹 ⋅ 𝑹 x = 1 𝑹
94 12 93 syl5 ⊢ y ∈ 𝑷 ∧ z ∈ 𝑷 → 0 𝑹 < 𝑹 y z ~ 𝑹 → ∃ x ∈ 𝑹 y z ~ 𝑹 ⋅ 𝑹 x = 1 𝑹
95 4 9 94 ecoptocl ⊢ A ∈ 𝑹 → 0 𝑹 < 𝑹 A → ∃ x ∈ 𝑹 A ⋅ 𝑹 x = 1 𝑹
96 3 95 mpcom ⊢ 0 𝑹 < 𝑹 A → ∃ x ∈ 𝑹 A ⋅ 𝑹 x = 1 𝑹