Description: Closure law for reciprocal. (Contributed by NM, 30-Apr-2005)
Ref | Expression | ||
---|---|---|---|
Hypothesis | redivcl.1 | |- A e. RR |
|
Assertion | rerecclzi | |- ( A =/= 0 -> ( 1 / A ) e. RR ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | redivcl.1 | |- A e. RR |
|
2 | rereccl | |- ( ( A e. RR /\ A =/= 0 ) -> ( 1 / A ) e. RR ) |
|
3 | 1 2 | mpan | |- ( A =/= 0 -> ( 1 / A ) e. RR ) |