Description: Closure law for reciprocal. (Contributed by Mario Carneiro, 27-May-2016)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | redivcld.1 | |- ( ph -> A e. RR ) |
|
| rereccld.2 | |- ( ph -> A =/= 0 ) |
||
| Assertion | rereccld | |- ( ph -> ( 1 / A ) e. RR ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | redivcld.1 | |- ( ph -> A e. RR ) |
|
| 2 | rereccld.2 | |- ( ph -> A =/= 0 ) |
|
| 3 | rereccl | |- ( ( A e. RR /\ A =/= 0 ) -> ( 1 / A ) e. RR ) |
|
| 4 | 1 2 3 | syl2anc | |- ( ph -> ( 1 / A ) e. RR ) |