Theorem pwpwssunieq 3896

Description: The class of sets whose union is equal to a given class is included in the double power class of that class. (Contributed by BJ, 29-Apr-2021.)

Assertion

Ref	Expression
pwpwssunieq	|- { x | U. x = A } C_ ~P ~P A

Distinct variable group:   x, A

Proof of Theorem pwpwssunieq

Step	Hyp	Ref	Expression
1		eqimss 3146	. . 3 |- ( U. x = A -> U. x C_ A )
2	1	ss2abi 3164	. 2 |- { x | U. x = A } C_ { x | U. x C_ A }
3		pwpwab 3895	. 2 |- ~P ~P A = { x | U. x C_ A }
4	2, 3	sseqtrri 3127	1 |- { x | U. x = A } C_ ~P ~P A

Syntax hints:   = wceq 1331   {cab 2123   C_ wss 3066   ~Pcpw 3505   U.cuni 3731

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 698  ax-5 1423  ax-7 1424  ax-gen 1425  ax-ie1 1469  ax-ie2 1470  ax-8 1482  ax-10 1483  ax-11 1484  ax-i12 1485  ax-bndl 1486  ax-4 1487  ax-17 1506  ax-i9 1510  ax-ial 1514  ax-i5r 1515  ax-ext 2119

This theorem depends on definitions:  df-bi 116  df-tru 1334  df-nf 1437  df-sb 1736  df-clab 2124  df-cleq 2130  df-clel 2133  df-nfc 2268  df-ral 2419  df-v 2683  df-in 3072  df-ss 3079  df-pw 3507  df-uni 3732

This theorem is referenced by:  toponsspwpwg  12178  dmtopon  12179