Metamath Proof Explorer


Theorem mndifsplit

Description: Lemma for maducoeval2 . (Contributed by SO, 16-Jul-2018)

Ref Expression
Hypotheses mndifsplit.b B=BaseM
mndifsplit.0g 0˙=0M
mndifsplit.pg +˙=+M
Assertion mndifsplit MMndAB¬φψifφψA0˙=ifφA0˙+˙ifψA0˙

Proof

Step Hyp Ref Expression
1 mndifsplit.b B=BaseM
2 mndifsplit.0g 0˙=0M
3 mndifsplit.pg +˙=+M
4 pm2.21 ¬φψφψifφψA0˙=ifφA0˙+˙ifψA0˙
5 4 imp ¬φψφψifφψA0˙=ifφA0˙+˙ifψA0˙
6 5 3ad2antl3 MMndAB¬φψφψifφψA0˙=ifφA0˙+˙ifψA0˙
7 1 3 2 mndrid MMndABA+˙0˙=A
8 7 3adant3 MMndAB¬φψA+˙0˙=A
9 8 adantr MMndAB¬φψφ¬ψA+˙0˙=A
10 iftrue φifφA0˙=A
11 iffalse ¬ψifψA0˙=0˙
12 10 11 oveqan12d φ¬ψifφA0˙+˙ifψA0˙=A+˙0˙
13 12 adantl MMndAB¬φψφ¬ψifφA0˙+˙ifψA0˙=A+˙0˙
14 iftrue φψifφψA0˙=A
15 14 orcs φifφψA0˙=A
16 15 ad2antrl MMndAB¬φψφ¬ψifφψA0˙=A
17 9 13 16 3eqtr4rd MMndAB¬φψφ¬ψifφψA0˙=ifφA0˙+˙ifψA0˙
18 1 3 2 mndlid MMndAB0˙+˙A=A
19 18 3adant3 MMndAB¬φψ0˙+˙A=A
20 19 adantr MMndAB¬φψ¬φψ0˙+˙A=A
21 iffalse ¬φifφA0˙=0˙
22 iftrue ψifψA0˙=A
23 21 22 oveqan12d ¬φψifφA0˙+˙ifψA0˙=0˙+˙A
24 23 adantl MMndAB¬φψ¬φψifφA0˙+˙ifψA0˙=0˙+˙A
25 14 olcs ψifφψA0˙=A
26 25 ad2antll MMndAB¬φψ¬φψifφψA0˙=A
27 20 24 26 3eqtr4rd MMndAB¬φψ¬φψifφψA0˙=ifφA0˙+˙ifψA0˙
28 simp1 MMndAB¬φψMMnd
29 1 2 mndidcl MMnd0˙B
30 1 3 2 mndlid MMnd0˙B0˙+˙0˙=0˙
31 28 29 30 syl2anc2 MMndAB¬φψ0˙+˙0˙=0˙
32 31 adantr MMndAB¬φψ¬φ¬ψ0˙+˙0˙=0˙
33 21 11 oveqan12d ¬φ¬ψifφA0˙+˙ifψA0˙=0˙+˙0˙
34 33 adantl MMndAB¬φψ¬φ¬ψifφA0˙+˙ifψA0˙=0˙+˙0˙
35 ioran ¬φψ¬φ¬ψ
36 iffalse ¬φψifφψA0˙=0˙
37 35 36 sylbir ¬φ¬ψifφψA0˙=0˙
38 37 adantl MMndAB¬φψ¬φ¬ψifφψA0˙=0˙
39 32 34 38 3eqtr4rd MMndAB¬φψ¬φ¬ψifφψA0˙=ifφA0˙+˙ifψA0˙
40 6 17 27 39 4casesdan MMndAB¬φψifφψA0˙=ifφA0˙+˙ifψA0˙