Metamath Proof Explorer


Theorem divreczi

Description: Relationship between division and reciprocal. Theorem I.9 of Apostol p. 18. (Contributed by NM, 11-Oct-1999)

Ref Expression
Hypotheses divclz.1
|- A e. CC
divclz.2
|- B e. CC
Assertion divreczi
|- ( B =/= 0 -> ( A / B ) = ( A x. ( 1 / B ) ) )

Proof

Step Hyp Ref Expression
1 divclz.1
 |-  A e. CC
2 divclz.2
 |-  B e. CC
3 divrec
 |-  ( ( A e. CC /\ B e. CC /\ B =/= 0 ) -> ( A / B ) = ( A x. ( 1 / B ) ) )
4 1 2 3 mp3an12
 |-  ( B =/= 0 -> ( A / B ) = ( A x. ( 1 / B ) ) )