Theorem disjdifb 48802

Description: Relative complement is anticommutative regarding intersection. (Contributed by Zhi Wang, 5-Sep-2024.)

Assertion

Ref	Expression
disjdifb	⊢ ((𝐴 ∖ 𝐵) ∩ (𝐵 ∖ 𝐴)) = ∅

Proof of Theorem disjdifb

Step	Hyp	Ref	Expression
1		indif1 4248	. 2 ⊢ ((𝐴 ∖ 𝐵) ∩ (𝐵 ∖ 𝐴)) = ((𝐴 ∩ (𝐵 ∖ 𝐴)) ∖ 𝐵)
2		disjdif 4438	. . 3 ⊢ (𝐴 ∩ (𝐵 ∖ 𝐴)) = ∅
3	2	difeq1i 4088	. 2 ⊢ ((𝐴 ∩ (𝐵 ∖ 𝐴)) ∖ 𝐵) = (∅ ∖ 𝐵)
4		0dif 4371	. 2 ⊢ (∅ ∖ 𝐵) = ∅
5	1, 3, 4	3eqtri 2757	1 ⊢ ((𝐴 ∖ 𝐵) ∩ (𝐵 ∖ 𝐴)) = ∅

Syntax hints:   = wceq 1540   ∖ cdif 3914   ∩ cin 3916  ∅c0 4299

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1967  ax-7 2008  ax-8 2111  ax-9 2119  ax-ext 2702

This theorem depends on definitions:  df-bi 207  df-an 396  df-tru 1543  df-fal 1553  df-ex 1780  df-sb 2066  df-clab 2709  df-cleq 2722  df-clel 2804  df-rab 3409  df-v 3452  df-dif 3920  df-in 3924  df-ss 3934  df-nul 4300

This theorem is referenced by:  iscnrm3r  48940