Step |
Hyp |
Ref |
Expression |
1 |
|
rrx2pnecoorneor.i |
|- I = { 1 , 2 } |
2 |
|
rrx2pnecoorneor.b |
|- P = ( RR ^m I ) |
3 |
|
rrx2pnedifcoorneor.a |
|- A = ( ( Y ` 1 ) - ( X ` 1 ) ) |
4 |
|
rrx2pnedifcoorneorr.b |
|- B = ( ( X ` 2 ) - ( Y ` 2 ) ) |
5 |
|
eqid |
|- ( ( Y ` 2 ) - ( X ` 2 ) ) = ( ( Y ` 2 ) - ( X ` 2 ) ) |
6 |
1 2 3 5
|
rrx2pnedifcoorneor |
|- ( ( X e. P /\ Y e. P /\ X =/= Y ) -> ( A =/= 0 \/ ( ( Y ` 2 ) - ( X ` 2 ) ) =/= 0 ) ) |
7 |
|
eqcom |
|- ( ( Y ` 2 ) = ( X ` 2 ) <-> ( X ` 2 ) = ( Y ` 2 ) ) |
8 |
7
|
a1i |
|- ( ( X e. P /\ Y e. P /\ X =/= Y ) -> ( ( Y ` 2 ) = ( X ` 2 ) <-> ( X ` 2 ) = ( Y ` 2 ) ) ) |
9 |
1 2
|
rrx2pyel |
|- ( X e. P -> ( X ` 2 ) e. RR ) |
10 |
9
|
recnd |
|- ( X e. P -> ( X ` 2 ) e. CC ) |
11 |
1 2
|
rrx2pyel |
|- ( Y e. P -> ( Y ` 2 ) e. RR ) |
12 |
11
|
recnd |
|- ( Y e. P -> ( Y ` 2 ) e. CC ) |
13 |
10 12
|
anim12i |
|- ( ( X e. P /\ Y e. P ) -> ( ( X ` 2 ) e. CC /\ ( Y ` 2 ) e. CC ) ) |
14 |
13
|
ancomd |
|- ( ( X e. P /\ Y e. P ) -> ( ( Y ` 2 ) e. CC /\ ( X ` 2 ) e. CC ) ) |
15 |
14
|
3adant3 |
|- ( ( X e. P /\ Y e. P /\ X =/= Y ) -> ( ( Y ` 2 ) e. CC /\ ( X ` 2 ) e. CC ) ) |
16 |
|
subeq0 |
|- ( ( ( Y ` 2 ) e. CC /\ ( X ` 2 ) e. CC ) -> ( ( ( Y ` 2 ) - ( X ` 2 ) ) = 0 <-> ( Y ` 2 ) = ( X ` 2 ) ) ) |
17 |
15 16
|
syl |
|- ( ( X e. P /\ Y e. P /\ X =/= Y ) -> ( ( ( Y ` 2 ) - ( X ` 2 ) ) = 0 <-> ( Y ` 2 ) = ( X ` 2 ) ) ) |
18 |
13
|
3adant3 |
|- ( ( X e. P /\ Y e. P /\ X =/= Y ) -> ( ( X ` 2 ) e. CC /\ ( Y ` 2 ) e. CC ) ) |
19 |
|
subeq0 |
|- ( ( ( X ` 2 ) e. CC /\ ( Y ` 2 ) e. CC ) -> ( ( ( X ` 2 ) - ( Y ` 2 ) ) = 0 <-> ( X ` 2 ) = ( Y ` 2 ) ) ) |
20 |
18 19
|
syl |
|- ( ( X e. P /\ Y e. P /\ X =/= Y ) -> ( ( ( X ` 2 ) - ( Y ` 2 ) ) = 0 <-> ( X ` 2 ) = ( Y ` 2 ) ) ) |
21 |
8 17 20
|
3bitr4d |
|- ( ( X e. P /\ Y e. P /\ X =/= Y ) -> ( ( ( Y ` 2 ) - ( X ` 2 ) ) = 0 <-> ( ( X ` 2 ) - ( Y ` 2 ) ) = 0 ) ) |
22 |
4
|
eqcomi |
|- ( ( X ` 2 ) - ( Y ` 2 ) ) = B |
23 |
22
|
eqeq1i |
|- ( ( ( X ` 2 ) - ( Y ` 2 ) ) = 0 <-> B = 0 ) |
24 |
21 23
|
bitrdi |
|- ( ( X e. P /\ Y e. P /\ X =/= Y ) -> ( ( ( Y ` 2 ) - ( X ` 2 ) ) = 0 <-> B = 0 ) ) |
25 |
24
|
necon3bid |
|- ( ( X e. P /\ Y e. P /\ X =/= Y ) -> ( ( ( Y ` 2 ) - ( X ` 2 ) ) =/= 0 <-> B =/= 0 ) ) |
26 |
25
|
orbi2d |
|- ( ( X e. P /\ Y e. P /\ X =/= Y ) -> ( ( A =/= 0 \/ ( ( Y ` 2 ) - ( X ` 2 ) ) =/= 0 ) <-> ( A =/= 0 \/ B =/= 0 ) ) ) |
27 |
6 26
|
mpbid |
|- ( ( X e. P /\ Y e. P /\ X =/= Y ) -> ( A =/= 0 \/ B =/= 0 ) ) |