Description: Closure law for subtraction. (Contributed by NM, 26-Nov-1994) (Revised by Mario Carneiro, 21-Dec-2013)
Ref | Expression | ||
---|---|---|---|
Hypotheses | negidi.1 | |- A e. CC |
|
pncan3i.2 | |- B e. CC |
||
Assertion | subcli | |- ( A - B ) e. CC |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | negidi.1 | |- A e. CC |
|
2 | pncan3i.2 | |- B e. CC |
|
3 | subcl | |- ( ( A e. CC /\ B e. CC ) -> ( A - B ) e. CC ) |
|
4 | 1 2 3 | mp2an | |- ( A - B ) e. CC |