Metamath Proof Explorer


Theorem addinvcom

Description: A number commutes with its additive inverse. Compare remulinvcom . (Contributed by SN, 5-May-2024)

Ref Expression
Hypotheses addinvcom.a φA
addinvcom.b φB
addinvcom.1 φA+B=0
Assertion addinvcom φB+A=0

Proof

Step Hyp Ref Expression
1 addinvcom.a φA
2 addinvcom.b φB
3 addinvcom.1 φA+B=0
4 ssidd φ
5 simpl A+x=0x+A=0A+x=0
6 5 rgenw xA+x=0x+A=0A+x=0
7 6 a1i φxA+x=0x+A=0A+x=0
8 sn-negex12 AxA+x=0x+A=0
9 1 8 syl φxA+x=0x+A=0
10 0cn 0
11 sn-subeu A0∃!xA+x=0
12 1 10 11 sylancl φ∃!xA+x=0
13 riotass2 xA+x=0x+A=0A+x=0xA+x=0x+A=0∃!xA+x=0ιx|A+x=0x+A=0=ιx|A+x=0
14 4 7 9 12 13 syl22anc φιx|A+x=0x+A=0=ιx|A+x=0
15 oveq2 x=BA+x=A+B
16 15 eqeq1d x=BA+x=0A+B=0
17 16 riota2 B∃!xA+x=0A+B=0ιx|A+x=0=B
18 2 12 17 syl2anc φA+B=0ιx|A+x=0=B
19 3 18 mpbid φιx|A+x=0=B
20 14 19 eqtrd φιx|A+x=0x+A=0=B
21 reurmo ∃!xA+x=0*xA+x=0
22 5 rmoimi *xA+x=0*xA+x=0x+A=0
23 12 21 22 3syl φ*xA+x=0x+A=0
24 reu5 ∃!xA+x=0x+A=0xA+x=0x+A=0*xA+x=0x+A=0
25 9 23 24 sylanbrc φ∃!xA+x=0x+A=0
26 oveq1 x=Bx+A=B+A
27 26 eqeq1d x=Bx+A=0B+A=0
28 16 27 anbi12d x=BA+x=0x+A=0A+B=0B+A=0
29 28 riota2 B∃!xA+x=0x+A=0A+B=0B+A=0ιx|A+x=0x+A=0=B
30 2 25 29 syl2anc φA+B=0B+A=0ιx|A+x=0x+A=0=B
31 20 30 mpbird φA+B=0B+A=0
32 31 simprd φB+A=0