Metamath Proof Explorer


Theorem brsset

Description: For sets, the SSet binary relation is equivalent to the subset relationship. (Contributed by Scott Fenton, 31-Mar-2012)

Ref Expression
Hypothesis brsset.1 B V
Assertion brsset A 𝖲𝖲𝖾𝗍 B A B

Proof

Step Hyp Ref Expression
1 brsset.1 B V
2 relsset Rel 𝖲𝖲𝖾𝗍
3 2 brrelex1i A 𝖲𝖲𝖾𝗍 B A V
4 1 ssex A B A V
5 breq1 x = A x 𝖲𝖲𝖾𝗍 B A 𝖲𝖲𝖾𝗍 B
6 sseq1 x = A x B A B
7 opex x B V
8 7 elrn x B ran E V E y y E V E x B
9 vex y V
10 vex x V
11 9 10 1 brtxp y E V E x B y E x y V E B
12 epel y E x y x
13 brv y V B
14 brdif y V E B y V B ¬ y E B
15 13 14 mpbiran y V E B ¬ y E B
16 1 epeli y E B y B
17 15 16 xchbinx y V E B ¬ y B
18 12 17 anbi12i y E x y V E B y x ¬ y B
19 11 18 bitri y E V E x B y x ¬ y B
20 19 exbii y y E V E x B y y x ¬ y B
21 exanali y y x ¬ y B ¬ y y x y B
22 8 20 21 3bitrri ¬ y y x y B x B ran E V E
23 22 con1bii ¬ x B ran E V E y y x y B
24 df-br x 𝖲𝖲𝖾𝗍 B x B 𝖲𝖲𝖾𝗍
25 df-sset 𝖲𝖲𝖾𝗍 = V × V ran E V E
26 25 eleq2i x B 𝖲𝖲𝖾𝗍 x B V × V ran E V E
27 10 1 opelvv x B V × V
28 eldif x B V × V ran E V E x B V × V ¬ x B ran E V E
29 27 28 mpbiran x B V × V ran E V E ¬ x B ran E V E
30 26 29 bitri x B 𝖲𝖲𝖾𝗍 ¬ x B ran E V E
31 24 30 bitri x 𝖲𝖲𝖾𝗍 B ¬ x B ran E V E
32 dfss2 x B y y x y B
33 23 31 32 3bitr4i x 𝖲𝖲𝖾𝗍 B x B
34 5 6 33 vtoclbg A V A 𝖲𝖲𝖾𝗍 B A B
35 3 4 34 pm5.21nii A 𝖲𝖲𝖾𝗍 B A B