Metamath Proof Explorer


Theorem dmgmdivn0

Description: Lemma for lgamf . (Contributed by Mario Carneiro, 3-Jul-2017)

Ref Expression
Hypotheses dmgmn0.a
|- ( ph -> A e. ( CC \ ( ZZ \ NN ) ) )
dmgmdivn0.a
|- ( ph -> M e. NN )
Assertion dmgmdivn0
|- ( ph -> ( ( A / M ) + 1 ) =/= 0 )

Proof

Step Hyp Ref Expression
1 dmgmn0.a
 |-  ( ph -> A e. ( CC \ ( ZZ \ NN ) ) )
2 dmgmdivn0.a
 |-  ( ph -> M e. NN )
3 1 eldifad
 |-  ( ph -> A e. CC )
4 2 nncnd
 |-  ( ph -> M e. CC )
5 2 nnne0d
 |-  ( ph -> M =/= 0 )
6 3 4 4 5 divdird
 |-  ( ph -> ( ( A + M ) / M ) = ( ( A / M ) + ( M / M ) ) )
7 4 5 dividd
 |-  ( ph -> ( M / M ) = 1 )
8 7 oveq2d
 |-  ( ph -> ( ( A / M ) + ( M / M ) ) = ( ( A / M ) + 1 ) )
9 6 8 eqtrd
 |-  ( ph -> ( ( A + M ) / M ) = ( ( A / M ) + 1 ) )
10 3 4 addcld
 |-  ( ph -> ( A + M ) e. CC )
11 2 nnnn0d
 |-  ( ph -> M e. NN0 )
12 dmgmaddn0
 |-  ( ( A e. ( CC \ ( ZZ \ NN ) ) /\ M e. NN0 ) -> ( A + M ) =/= 0 )
13 1 11 12 syl2anc
 |-  ( ph -> ( A + M ) =/= 0 )
14 10 4 13 5 divne0d
 |-  ( ph -> ( ( A + M ) / M ) =/= 0 )
15 9 14 eqnetrrd
 |-  ( ph -> ( ( A / M ) + 1 ) =/= 0 )