Description: The converse of the adjoint function is a function. (Contributed by NM, 25-Jan-2006) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | funcnvadj | ⊢ Fun ◡ adjℎ | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | funadj | ⊢ Fun adjℎ | |
| 2 | cnvadj | ⊢ ◡ adjℎ = adjℎ | |
| 3 | 2 | funeqi | ⊢ ( Fun ◡ adjℎ ↔ Fun adjℎ ) | 
| 4 | 1 3 | mpbir | ⊢ Fun ◡ adjℎ |