Description: A number divided by itself is one. (Contributed by NM, 1-Aug-2004)
Ref | Expression | ||
---|---|---|---|
Assertion | divid | |- ( ( A e. CC /\ A =/= 0 ) -> ( A / A ) = 1 ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | divrec | |- ( ( A e. CC /\ A e. CC /\ A =/= 0 ) -> ( A / A ) = ( A x. ( 1 / A ) ) ) |
|
2 | 1 | 3anidm12 | |- ( ( A e. CC /\ A =/= 0 ) -> ( A / A ) = ( A x. ( 1 / A ) ) ) |
3 | recid | |- ( ( A e. CC /\ A =/= 0 ) -> ( A x. ( 1 / A ) ) = 1 ) |
|
4 | 2 3 | eqtrd | |- ( ( A e. CC /\ A =/= 0 ) -> ( A / A ) = 1 ) |