Description: The union of a chain (with respect to inclusion) of one-to-one functions is a one-to-one function. (Contributed by NM, 11-Aug-2004)
Ref | Expression | ||
---|---|---|---|
Assertion | fun11uni | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | simpl | |
|
2 | 1 | anim1i | |
3 | 2 | ralimi | |
4 | fununi | |
|
5 | 3 4 | syl | |
6 | simpr | |
|
7 | 6 | anim1i | |
8 | 7 | ralimi | |
9 | funcnvuni | |
|
10 | 8 9 | syl | |
11 | 5 10 | jca | |