This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.
Description: Addition is commutative for integers. Proven without ax-mulcom . (Contributed by SN, 25-Jan-2025)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | zaddcom | |- ( ( A e. ZZ /\ B e. ZZ ) -> ( A + B ) = ( B + A ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | reelznn0nn | |- ( A e. ZZ <-> ( A e. NN0 \/ ( A e. RR /\ ( 0 -R A ) e. NN ) ) ) |
|
| 2 | reelznn0nn | |- ( B e. ZZ <-> ( B e. NN0 \/ ( B e. RR /\ ( 0 -R B ) e. NN ) ) ) |
|
| 3 | nn0addcom | |- ( ( A e. NN0 /\ B e. NN0 ) -> ( A + B ) = ( B + A ) ) |
|
| 4 | zaddcomlem | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ B e. NN0 ) -> ( A + B ) = ( B + A ) ) |
|
| 5 | zaddcomlem | |- ( ( ( B e. RR /\ ( 0 -R B ) e. NN ) /\ A e. NN0 ) -> ( B + A ) = ( A + B ) ) |
|
| 6 | 5 | eqcomd | |- ( ( ( B e. RR /\ ( 0 -R B ) e. NN ) /\ A e. NN0 ) -> ( A + B ) = ( B + A ) ) |
| 7 | 6 | ancoms | |- ( ( A e. NN0 /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( A + B ) = ( B + A ) ) |
| 8 | renegid2 | |- ( B e. RR -> ( ( 0 -R B ) + B ) = 0 ) |
|
| 9 | 8 | ad2antrl | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( ( 0 -R B ) + B ) = 0 ) |
| 10 | renegid2 | |- ( A e. RR -> ( ( 0 -R A ) + A ) = 0 ) |
|
| 11 | 10 | ad2antrr | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( ( 0 -R A ) + A ) = 0 ) |
| 12 | 11 | oveq1d | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( ( ( 0 -R A ) + A ) + B ) = ( 0 + B ) ) |
| 13 | simplr | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( 0 -R A ) e. NN ) |
|
| 14 | 13 | nncnd | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( 0 -R A ) e. CC ) |
| 15 | simpll | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> A e. RR ) |
|
| 16 | 15 | recnd | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> A e. CC ) |
| 17 | simprl | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> B e. RR ) |
|
| 18 | 17 | recnd | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> B e. CC ) |
| 19 | 14 16 18 | addassd | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( ( ( 0 -R A ) + A ) + B ) = ( ( 0 -R A ) + ( A + B ) ) ) |
| 20 | readdlid | |- ( B e. RR -> ( 0 + B ) = B ) |
|
| 21 | 20 | ad2antrl | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( 0 + B ) = B ) |
| 22 | 12 19 21 | 3eqtr3d | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( ( 0 -R A ) + ( A + B ) ) = B ) |
| 23 | 22 | oveq2d | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( ( 0 -R B ) + ( ( 0 -R A ) + ( A + B ) ) ) = ( ( 0 -R B ) + B ) ) |
| 24 | 9 23 11 | 3eqtr4d | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( ( 0 -R B ) + ( ( 0 -R A ) + ( A + B ) ) ) = ( ( 0 -R A ) + A ) ) |
| 25 | simprr | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( 0 -R B ) e. NN ) |
|
| 26 | 25 | nncnd | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( 0 -R B ) e. CC ) |
| 27 | 16 18 | addcld | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( A + B ) e. CC ) |
| 28 | 26 14 27 | addassd | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( ( ( 0 -R B ) + ( 0 -R A ) ) + ( A + B ) ) = ( ( 0 -R B ) + ( ( 0 -R A ) + ( A + B ) ) ) ) |
| 29 | 9 | oveq1d | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( ( ( 0 -R B ) + B ) + A ) = ( 0 + A ) ) |
| 30 | 26 18 16 | addassd | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( ( ( 0 -R B ) + B ) + A ) = ( ( 0 -R B ) + ( B + A ) ) ) |
| 31 | readdlid | |- ( A e. RR -> ( 0 + A ) = A ) |
|
| 32 | 31 | ad2antrr | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( 0 + A ) = A ) |
| 33 | 29 30 32 | 3eqtr3d | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( ( 0 -R B ) + ( B + A ) ) = A ) |
| 34 | 33 | oveq2d | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( ( 0 -R A ) + ( ( 0 -R B ) + ( B + A ) ) ) = ( ( 0 -R A ) + A ) ) |
| 35 | 24 28 34 | 3eqtr4d | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( ( ( 0 -R B ) + ( 0 -R A ) ) + ( A + B ) ) = ( ( 0 -R A ) + ( ( 0 -R B ) + ( B + A ) ) ) ) |
| 36 | nnaddcom | |- ( ( ( 0 -R A ) e. NN /\ ( 0 -R B ) e. NN ) -> ( ( 0 -R A ) + ( 0 -R B ) ) = ( ( 0 -R B ) + ( 0 -R A ) ) ) |
|
| 37 | 36 | ad2ant2l | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( ( 0 -R A ) + ( 0 -R B ) ) = ( ( 0 -R B ) + ( 0 -R A ) ) ) |
| 38 | 37 | oveq1d | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( ( ( 0 -R A ) + ( 0 -R B ) ) + ( A + B ) ) = ( ( ( 0 -R B ) + ( 0 -R A ) ) + ( A + B ) ) ) |
| 39 | 18 16 | addcld | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( B + A ) e. CC ) |
| 40 | 14 26 39 | addassd | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( ( ( 0 -R A ) + ( 0 -R B ) ) + ( B + A ) ) = ( ( 0 -R A ) + ( ( 0 -R B ) + ( B + A ) ) ) ) |
| 41 | 35 38 40 | 3eqtr4d | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( ( ( 0 -R A ) + ( 0 -R B ) ) + ( A + B ) ) = ( ( ( 0 -R A ) + ( 0 -R B ) ) + ( B + A ) ) ) |
| 42 | 13 25 | nnaddcld | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( ( 0 -R A ) + ( 0 -R B ) ) e. NN ) |
| 43 | 42 | nncnd | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( ( 0 -R A ) + ( 0 -R B ) ) e. CC ) |
| 44 | 43 27 39 | sn-addcand | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( ( ( ( 0 -R A ) + ( 0 -R B ) ) + ( A + B ) ) = ( ( ( 0 -R A ) + ( 0 -R B ) ) + ( B + A ) ) <-> ( A + B ) = ( B + A ) ) ) |
| 45 | 41 44 | mpbid | |- ( ( ( A e. RR /\ ( 0 -R A ) e. NN ) /\ ( B e. RR /\ ( 0 -R B ) e. NN ) ) -> ( A + B ) = ( B + A ) ) |
| 46 | 3 4 7 45 | ccase | |- ( ( ( A e. NN0 \/ ( A e. RR /\ ( 0 -R A ) e. NN ) ) /\ ( B e. NN0 \/ ( B e. RR /\ ( 0 -R B ) e. NN ) ) ) -> ( A + B ) = ( B + A ) ) |
| 47 | 1 2 46 | syl2anb | |- ( ( A e. ZZ /\ B e. ZZ ) -> ( A + B ) = ( B + A ) ) |