Theorem xpundi 4826

Description: Distributive law for cross product over union. Theorem 103 of [Suppes] p. 52. (Contributed by NM, 12-Aug-2004.)

Assertion

Ref	Expression
xpundi	|- ( A X. ( B u. C ) ) = ( ( A X. B ) u. ( A X. C ) )

Proof of Theorem xpundi

Dummy variables x y are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		df-xp 4775	. 2 |- ( A X. ( B u. C ) ) = { <. x , y >. | ( x e. A /\ y e. ( B u. C ) ) }
2		df-xp 4775	. . . 4 |- ( A X. B ) = { <. x , y >. | ( x e. A /\ y e. B ) }
3		df-xp 4775	. . . 4 |- ( A X. C ) = { <. x , y >. | ( x e. A /\ y e. C ) }
4	2, 3	uneq12i 3381	. . 3 |- ( ( A X. B ) u. ( A X. C ) ) = ( { <. x , y >. | ( x e. A /\ y e. B ) } u. { <. x , y >. | ( x e. A /\ y e. C ) } )
5		elun 3370	. . . . . . 7 |- ( y e. ( B u. C ) <-> ( y e. B \/ y e. C ) )
6	5	anbi2i 461	. . . . . 6 |- ( ( x e. A /\ y e. ( B u. C ) ) <-> ( x e. A /\ ( y e. B \/ y e. C ) ) )
7		andi 830	. . . . . 6 |- ( ( x e. A /\ ( y e. B \/ y e. C ) ) <-> ( ( x e. A /\ y e. B ) \/ ( x e. A /\ y e. C ) ) )
8	6, 7	bitri 184	. . . . 5 |- ( ( x e. A /\ y e. ( B u. C ) ) <-> ( ( x e. A /\ y e. B ) \/ ( x e. A /\ y e. C ) ) )
9	8	opabbii 4193	. . . 4 |- { <. x , y >. | ( x e. A /\ y e. ( B u. C ) ) } = { <. x , y >. | ( ( x e. A /\ y e. B ) \/ ( x e. A /\ y e. C ) ) }
10		unopab 4205	. . . 4 |- ( { <. x , y >. | ( x e. A /\ y e. B ) } u. { <. x , y >. | ( x e. A /\ y e. C ) } ) = { <. x , y >. | ( ( x e. A /\ y e. B ) \/ ( x e. A /\ y e. C ) ) }
11	9, 10	eqtr4i 2262	. . 3 |- { <. x , y >. | ( x e. A /\ y e. ( B u. C ) ) } = ( { <. x , y >. | ( x e. A /\ y e. B ) } u. { <. x , y >. | ( x e. A /\ y e. C ) } )
12	4, 11	eqtr4i 2262	. 2 |- ( ( A X. B ) u. ( A X. C ) ) = { <. x , y >. | ( x e. A /\ y e. ( B u. C ) ) }
13	1, 12	eqtr4i 2262	1 |- ( A X. ( B u. C ) ) = ( ( A X. B ) u. ( A X. C ) )

Syntax hints:   /\ wa 104   \/ wo 720   = wceq 1402   e. wcel 2209   u. cun 3218   {copab 4186   X. cxp 4767

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-ext 2220

This theorem depends on definitions:  df-bi 117  df-tru 1405  df-nf 1514  df-sb 1816  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-v 2823  df-un 3224  df-opab 4188  df-xp 4775

This theorem is referenced by:  xpun  4831  djuassen  7563  xpdjuen  7564