theorem nfmax {x: nat} (a b: nat x):
$ FN/ x a $ >
$ FN/ x b $ >
$ FN/ x max a b $;
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | anl | u = a /\ v = b -> u = a |
|
| 2 | anr | u = a /\ v = b -> v = b |
|
| 3 | 1, 2 | maxeqd | u = a /\ v = b -> max u v = max a b |
| 4 | hyp h1 | FN/ x a |
|
| 5 | hyp h2 | FN/ x b |
|
| 6 | 3, 4, 5 | nfnlem2 | FN/ x max a b |