Metamath Proof Explorer


Theorem spansneleq

Description: Membership relation that implies equality of spans. (Contributed by NM, 6-Jun-2004) (New usage is discouraged.)

Ref Expression
Assertion spansneleq B A 0 A span B span A = span B

Proof

Step Hyp Ref Expression
1 elspansn B A span B x A = x B
2 1 adantr B A 0 A span B x A = x B
3 sneq A = x B A = x B
4 3 fveq2d A = x B span A = span x B
5 4 ad2antll B A 0 x A = x B span A = span x B
6 oveq1 x = 0 x B = 0 B
7 ax-hvmul0 B 0 B = 0
8 6 7 sylan9eqr B x = 0 x B = 0
9 8 ex B x = 0 x B = 0
10 eqeq1 A = x B A = 0 x B = 0
11 10 biimprd A = x B x B = 0 A = 0
12 9 11 sylan9 B A = x B x = 0 A = 0
13 12 necon3d B A = x B A 0 x 0
14 13 ex B A = x B A 0 x 0
15 14 com23 B A 0 A = x B x 0
16 15 impd B A 0 A = x B x 0
17 16 adantr B x A 0 A = x B x 0
18 spansncol B x x 0 span x B = span B
19 18 3expia B x x 0 span x B = span B
20 17 19 syld B x A 0 A = x B span x B = span B
21 20 exp4b B x A 0 A = x B span x B = span B
22 21 com23 B A 0 x A = x B span x B = span B
23 22 imp43 B A 0 x A = x B span x B = span B
24 5 23 eqtrd B A 0 x A = x B span A = span B
25 24 rexlimdvaa B A 0 x A = x B span A = span B
26 2 25 sylbid B A 0 A span B span A = span B