Metamath Proof Explorer


Theorem nfinf

Description: Hypothesis builder for infimum. (Contributed by AV, 2-Sep-2020)

Ref Expression
Hypotheses nfinf.1 𝑥 𝐴
nfinf.2 𝑥 𝐵
nfinf.3 𝑥 𝑅
Assertion nfinf 𝑥 inf ( 𝐴 , 𝐵 , 𝑅 )

Proof

Step Hyp Ref Expression
1 nfinf.1 𝑥 𝐴
2 nfinf.2 𝑥 𝐵
3 nfinf.3 𝑥 𝑅
4 df-inf inf ( 𝐴 , 𝐵 , 𝑅 ) = sup ( 𝐴 , 𝐵 , 𝑅 )
5 3 nfcnv 𝑥 𝑅
6 1 2 5 nfsup 𝑥 sup ( 𝐴 , 𝐵 , 𝑅 )
7 4 6 nfcxfr 𝑥 inf ( 𝐴 , 𝐵 , 𝑅 )