Database
ZF (ZERMELO-FRAENKEL) SET THEORY
ZF Set Theory - add the Axiom of Union
Function transposition
df-tpos
Metamath Proof Explorer
Description: Define the transposition of a function, which is a function
G = tpos F satisfying G ( x , y ) = F ( y , x ) . (Contributed by Mario Carneiro , 10-Sep-2015)
Ref
Expression
Assertion
df-tpos
|- tpos F = ( F o. ( x e. ( `' dom F u. { (/) } ) |-> U. `' { x } ) )
Detailed syntax breakdown
Step
Hyp
Ref
Expression
0
cF
|- F
1
0
ctpos
|- tpos F
2
vx
|- x
3
0
cdm
|- dom F
4
3
ccnv
|- `' dom F
5
c0
|- (/)
6
5
csn
|- { (/) }
7
4 6
cun
|- ( `' dom F u. { (/) } )
8
2
cv
|- x
9
8
csn
|- { x }
10
9
ccnv
|- `' { x }
11
10
cuni
|- U. `' { x }
12
2 7 11
cmpt
|- ( x e. ( `' dom F u. { (/) } ) |-> U. `' { x } )
13
0 12
ccom
|- ( F o. ( x e. ( `' dom F u. { (/) } ) |-> U. `' { x } ) )
14
1 13
wceq
|- tpos F = ( F o. ( x e. ( `' dom F u. { (/) } ) |-> U. `' { x } ) )