Theorem 4m1e3

Description: 4 - 1 = 3. (Contributed by AV, 8-Feb-2021) (Proof shortened by AV, 6-Sep-2021)

	Ref	Expression
Assertion	4m1e3	⊢ ( 4 − 1 ) = 3

Proof

Step	Hyp	Ref	Expression
1		3cn	⊢ 3 ∈ ℂ
2		ax-1cn	⊢ 1 ∈ ℂ
3		df-4	⊢ 4 = ( 3 + 1 )
4	1 2 3	mvrraddi	⊢ ( 4 − 1 ) = 3