Description: 2 is an integer greater than or equal to 1. (Contributed by Alexander van der Vekens, 8-Jun-2018)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | 2eluzge1 | ⊢ 2 ∈ ( ℤ≥ ‘ 1 ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | 1z | ⊢ 1 ∈ ℤ | |
| 2 | 2z | ⊢ 2 ∈ ℤ | |
| 3 | 1le2 | ⊢ 1 ≤ 2 | |
| 4 | eluz2 | ⊢ ( 2 ∈ ( ℤ≥ ‘ 1 ) ↔ ( 1 ∈ ℤ ∧ 2 ∈ ℤ ∧ 1 ≤ 2 ) ) | |
| 5 | 1 2 3 4 | mpbir3an | ⊢ 2 ∈ ( ℤ≥ ‘ 1 ) |