Description: Hypothesis builder for infimum. (Contributed by AV, 2-Sep-2020)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | nfinf.1 | ⊢ Ⅎ 𝑥 𝐴 | |
| nfinf.2 | ⊢ Ⅎ 𝑥 𝐵 | ||
| nfinf.3 | ⊢ Ⅎ 𝑥 𝑅 | ||
| Assertion | nfinf | ⊢ Ⅎ 𝑥 inf ( 𝐴 , 𝐵 , 𝑅 ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | nfinf.1 | ⊢ Ⅎ 𝑥 𝐴 | |
| 2 | nfinf.2 | ⊢ Ⅎ 𝑥 𝐵 | |
| 3 | nfinf.3 | ⊢ Ⅎ 𝑥 𝑅 | |
| 4 | df-inf | ⊢ inf ( 𝐴 , 𝐵 , 𝑅 ) = sup ( 𝐴 , 𝐵 , ◡ 𝑅 ) | |
| 5 | 3 | nfcnv | ⊢ Ⅎ 𝑥 ◡ 𝑅 | 
| 6 | 1 2 5 | nfsup | ⊢ Ⅎ 𝑥 sup ( 𝐴 , 𝐵 , ◡ 𝑅 ) | 
| 7 | 4 6 | nfcxfr | ⊢ Ⅎ 𝑥 inf ( 𝐴 , 𝐵 , 𝑅 ) |