Description: Substitution with a variable not free in antecedent affects only the consequent. Closed form of sbrim . (Contributed by Wolf Lammen, 26-Jul-2019)
Ref | Expression | ||
---|---|---|---|
Assertion | wl-sblimt | |- ( F/ x ps -> ( [ y / x ] ( ph -> ps ) <-> ( [ y / x ] ph -> ps ) ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | sbim | |- ( [ y / x ] ( ph -> ps ) <-> ( [ y / x ] ph -> [ y / x ] ps ) ) |
|
2 | sbft | |- ( F/ x ps -> ( [ y / x ] ps <-> ps ) ) |
|
3 | 2 | imbi2d | |- ( F/ x ps -> ( ( [ y / x ] ph -> [ y / x ] ps ) <-> ( [ y / x ] ph -> ps ) ) ) |
4 | 1 3 | syl5bb | |- ( F/ x ps -> ( [ y / x ] ( ph -> ps ) <-> ( [ y / x ] ph -> ps ) ) ) |