Description: 7 + 5 = 12. (Contributed by Mario Carneiro, 19-Apr-2015)
Ref | Expression | ||
---|---|---|---|
Assertion | 7p5e12 | ⊢ ( 7 + 5 ) = ; 1 2 |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | 7nn0 | ⊢ 7 ∈ ℕ0 | |
2 | 4nn0 | ⊢ 4 ∈ ℕ0 | |
3 | 1nn0 | ⊢ 1 ∈ ℕ0 | |
4 | df-5 | ⊢ 5 = ( 4 + 1 ) | |
5 | df-2 | ⊢ 2 = ( 1 + 1 ) | |
6 | 7p4e11 | ⊢ ( 7 + 4 ) = ; 1 1 | |
7 | 1 2 3 4 5 6 | 6p5lem | ⊢ ( 7 + 5 ) = ; 1 2 |