Theorem 7p4e11

Description: 7 + 4 = 11. (Contributed by Mario Carneiro, 19-Apr-2015) (Revised by AV, 6-Sep-2021)

	Ref	Expression
Assertion	7p4e11	⊢ ( 7 + 4 ) = ; 1 1

Proof

Step	Hyp	Ref	Expression
1		7nn0	⊢ 7 ∈ ℕ0
2		3nn0	⊢ 3 ∈ ℕ0
3		0nn0	⊢ 0 ∈ ℕ0
4		df-4	⊢ 4 = ( 3 + 1 )
5		1e0p1	⊢ 1 = ( 0 + 1 )
6		7p3e10	⊢ ( 7 + 3 ) = ; 1 0
7	1 2 3 4 5 6	6p5lem	⊢ ( 7 + 4 ) = ; 1 1