Description: If a proposition is implied by x e.V and y e. V (which is true, see vex ), then it is true. (Contributed by Peter Mazsa, 13-Oct-2018)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | el2v.1 | |- ( ( x e. _V /\ y e. _V ) -> ph ) |
|
| Assertion | el2v | |- ph |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | el2v.1 | |- ( ( x e. _V /\ y e. _V ) -> ph ) |
|
| 2 | vex | |- x e. _V |
|
| 3 | vex | |- y e. _V |
|
| 4 | 2 3 1 | mp2an | |- ph |