Description: Distribute the unabbreviated form of proper substitution in and out of a conjunction. (Contributed by Alan Sare, 31-May-2014) (Proof modification is discouraged.) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | 2uasban | |- ( E. x E. y ( ( x = u /\ y = v ) /\ ( ph /\ ps ) ) <-> ( E. x E. y ( ( x = u /\ y = v ) /\ ph ) /\ E. x E. y ( ( x = u /\ y = v ) /\ ps ) ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | biid | |- ( ( E. x E. y ( ( x = u /\ y = v ) /\ ph ) /\ E. x E. y ( ( x = u /\ y = v ) /\ ps ) ) <-> ( E. x E. y ( ( x = u /\ y = v ) /\ ph ) /\ E. x E. y ( ( x = u /\ y = v ) /\ ps ) ) ) |
|
| 2 | 1 | 2uasbanh | |- ( E. x E. y ( ( x = u /\ y = v ) /\ ( ph /\ ps ) ) <-> ( E. x E. y ( ( x = u /\ y = v ) /\ ph ) /\ E. x E. y ( ( x = u /\ y = v ) /\ ps ) ) ) |