Description: The number 5 is positive. (Contributed by NM, 27-May-1999)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | 5pos | ⊢ 0 < 5 |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | 4re | ⊢ 4 ∈ ℝ | |
| 2 | 1re | ⊢ 1 ∈ ℝ | |
| 3 | 4pos | ⊢ 0 < 4 | |
| 4 | 0lt1 | ⊢ 0 < 1 | |
| 5 | 1 2 3 4 | addgt0ii | ⊢ 0 < ( 4 + 1 ) |
| 6 | df-5 | ⊢ 5 = ( 4 + 1 ) | |
| 7 | 5 6 | breqtrri | ⊢ 0 < 5 |