Description: Composition in the category of sets. (Contributed by Mario Carneiro, 3-Jan-2017)
Ref | Expression | ||
---|---|---|---|
Hypotheses | setcbas.c | |
|
setcbas.u | |
||
setcco.o | |
||
Assertion | setccofval | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | setcbas.c | |
|
2 | setcbas.u | |
|
3 | setcco.o | |
|
4 | eqid | |
|
5 | 1 2 4 | setchomfval | |
6 | eqidd | |
|
7 | 1 2 5 6 | setcval | |
8 | catstr | |
|
9 | ccoid | |
|
10 | snsstp3 | |
|
11 | 2 2 | xpexd | |
12 | mpoexga | |
|
13 | 11 2 12 | syl2anc | |
14 | 7 8 9 10 13 3 | strfv3 | |