Metamath Proof Explorer


Theorem divnegd

Description: Move negative sign inside of a division. (Contributed by Mario Carneiro, 27-May-2016)

Ref Expression
Hypotheses div1d.1
|- ( ph -> A e. CC )
divcld.2
|- ( ph -> B e. CC )
divcld.3
|- ( ph -> B =/= 0 )
Assertion divnegd
|- ( ph -> -u ( A / B ) = ( -u A / B ) )

Proof

Step Hyp Ref Expression
1 div1d.1
 |-  ( ph -> A e. CC )
2 divcld.2
 |-  ( ph -> B e. CC )
3 divcld.3
 |-  ( ph -> B =/= 0 )
4 divneg
 |-  ( ( A e. CC /\ B e. CC /\ B =/= 0 ) -> -u ( A / B ) = ( -u A / B ) )
5 1 2 3 4 syl3anc
 |-  ( ph -> -u ( A / B ) = ( -u A / B ) )