Description: 8 is less than 10. (Contributed by Mario Carneiro, 8-Feb-2015) (Revised by AV, 8-Sep-2021)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | 8lt10 | |- 8 < ; 1 0 | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | 8lt9 | |- 8 < 9 | |
| 2 | 9lt10 | |- 9 < ; 1 0 | |
| 3 | 8re | |- 8 e. RR | |
| 4 | 9re | |- 9 e. RR | |
| 5 | 10re | |- ; 1 0 e. RR | |
| 6 | 3 4 5 | lttri | |- ( ( 8 < 9 /\ 9 < ; 1 0 ) -> 8 < ; 1 0 ) | 
| 7 | 1 2 6 | mp2an | |- 8 < ; 1 0 |