Description: Relationship between division and reciprocal. (Contributed by NM, 7-Feb-2006)
Ref | Expression | ||
---|---|---|---|
Assertion | divrec2 | |- ( ( A e. CC /\ B e. CC /\ B =/= 0 ) -> ( A / B ) = ( ( 1 / B ) x. A ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | divrec | |- ( ( A e. CC /\ B e. CC /\ B =/= 0 ) -> ( A / B ) = ( A x. ( 1 / B ) ) ) |
|
2 | simp1 | |- ( ( A e. CC /\ B e. CC /\ B =/= 0 ) -> A e. CC ) |
|
3 | reccl | |- ( ( B e. CC /\ B =/= 0 ) -> ( 1 / B ) e. CC ) |
|
4 | 3 | 3adant1 | |- ( ( A e. CC /\ B e. CC /\ B =/= 0 ) -> ( 1 / B ) e. CC ) |
5 | 2 4 | mulcomd | |- ( ( A e. CC /\ B e. CC /\ B =/= 0 ) -> ( A x. ( 1 / B ) ) = ( ( 1 / B ) x. A ) ) |
6 | 1 5 | eqtrd | |- ( ( A e. CC /\ B e. CC /\ B =/= 0 ) -> ( A / B ) = ( ( 1 / B ) x. A ) ) |