Description: Existence of a difference, inference version of difexg . (Contributed by Glauco Siliprandi, 3-Mar-2021) (Revised by AV, 26-Mar-2021)
Ref | Expression | ||
---|---|---|---|
Hypothesis | difexi.1 | |- A e. _V |
|
Assertion | difexi | |- ( A \ B ) e. _V |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | difexi.1 | |- A e. _V |
|
2 | difexg | |- ( A e. _V -> ( A \ B ) e. _V ) |
|
3 | 1 2 | ax-mp | |- ( A \ B ) e. _V |