Metamath Proof Explorer


Theorem 0elright

Description: Zero is in the right set of any negative number. (Contributed by Scott Fenton, 13-Mar-2025)

Ref Expression
Hypotheses 0elright.1 φANo
0elright.2 φA<s0s
Assertion 0elright φ0sRA

Proof

Step Hyp Ref Expression
1 0elright.1 φANo
2 0elright.2 φA<s0s
3 sltne ANoA<s0s0sA
4 1 2 3 syl2anc φ0sA
5 4 necomd φA0s
6 1 5 0elold φ0sOldbdayA
7 breq2 x=0sA<sxA<s0s
8 rightval RA=xOldbdayA|A<sx
9 7 8 elrab2 0sRA0sOldbdayAA<s0s
10 6 2 9 sylanbrc φ0sRA