Step |
Hyp |
Ref |
Expression |
1 |
|
zcn |
|- ( B e. ZZ -> B e. CC ) |
2 |
1
|
3ad2ant2 |
|- ( ( A e. ZZ /\ B e. ZZ /\ D e. NN ) -> B e. CC ) |
3 |
|
zcn |
|- ( A e. ZZ -> A e. CC ) |
4 |
3
|
3ad2ant1 |
|- ( ( A e. ZZ /\ B e. ZZ /\ D e. NN ) -> A e. CC ) |
5 |
|
nncn |
|- ( D e. NN -> D e. CC ) |
6 |
|
nnne0 |
|- ( D e. NN -> D =/= 0 ) |
7 |
5 6
|
jca |
|- ( D e. NN -> ( D e. CC /\ D =/= 0 ) ) |
8 |
7
|
3ad2ant3 |
|- ( ( A e. ZZ /\ B e. ZZ /\ D e. NN ) -> ( D e. CC /\ D =/= 0 ) ) |
9 |
|
divass |
|- ( ( B e. CC /\ A e. CC /\ ( D e. CC /\ D =/= 0 ) ) -> ( ( B x. A ) / D ) = ( B x. ( A / D ) ) ) |
10 |
2 4 8 9
|
syl3anc |
|- ( ( A e. ZZ /\ B e. ZZ /\ D e. NN ) -> ( ( B x. A ) / D ) = ( B x. ( A / D ) ) ) |
11 |
10
|
3comr |
|- ( ( D e. NN /\ A e. ZZ /\ B e. ZZ ) -> ( ( B x. A ) / D ) = ( B x. ( A / D ) ) ) |
12 |
11
|
adantr |
|- ( ( ( D e. NN /\ A e. ZZ /\ B e. ZZ ) /\ ( A / D ) e. ZZ ) -> ( ( B x. A ) / D ) = ( B x. ( A / D ) ) ) |
13 |
|
zmulcl |
|- ( ( B e. ZZ /\ ( A / D ) e. ZZ ) -> ( B x. ( A / D ) ) e. ZZ ) |
14 |
13
|
3ad2antl3 |
|- ( ( ( D e. NN /\ A e. ZZ /\ B e. ZZ ) /\ ( A / D ) e. ZZ ) -> ( B x. ( A / D ) ) e. ZZ ) |
15 |
12 14
|
eqeltrd |
|- ( ( ( D e. NN /\ A e. ZZ /\ B e. ZZ ) /\ ( A / D ) e. ZZ ) -> ( ( B x. A ) / D ) e. ZZ ) |