Metamath Proof Explorer


Theorem addgtge0d

Description: Addition of positive and nonnegative numbers is positive. (Contributed by Asger C. Ipsen, 12-May-2021)

Ref Expression
Hypotheses leidd.1 φA
ltnegd.2 φB
addgtge0d.3 φ0<A
addgtge0d.4 φ0B
Assertion addgtge0d φ0<A+B

Proof

Step Hyp Ref Expression
1 leidd.1 φA
2 ltnegd.2 φB
3 addgtge0d.3 φ0<A
4 addgtge0d.4 φ0B
5 addgtge0 AB0<A0B0<A+B
6 1 2 3 4 5 syl22anc φ0<A+B