Theorem subidi

Description: Subtraction of a number from itself. (Contributed by NM, 26-Nov-1994)

	Ref	Expression
Hypothesis	negidi.1	⊢ 𝐴 ∈ ℂ
Assertion	subidi	⊢ ( 𝐴 − 𝐴 ) = 0

Proof

Step	Hyp	Ref	Expression
1		negidi.1	⊢ 𝐴 ∈ ℂ
2		subid	⊢ ( 𝐴 ∈ ℂ → ( 𝐴 − 𝐴 ) = 0 )
3	1 2	ax-mp	⊢ ( 𝐴 − 𝐴 ) = 0