theorem zadd02 (a: nat): $ a +Z 0 = a $;
Step | Hyp | Ref | Expression |
1 |
|
eqtr |
a +Z 0 = zfst a -ZN zsnd a -> zfst a -ZN zsnd a = a -> a +Z 0 = a |
2 |
|
znsubeq |
zfst a + zfst 0 = zfst a -> zsnd a + zsnd 0 = zsnd a -> zfst a + zfst 0 -ZN (zsnd a + zsnd 0) = zfst a -ZN zsnd a |
3 |
2 |
conv zadd |
zfst a + zfst 0 = zfst a -> zsnd a + zsnd 0 = zsnd a -> a +Z 0 = zfst a -ZN zsnd a |
4 |
|
eqtr |
zfst a + zfst 0 = zfst a + 0 -> zfst a + 0 = zfst a -> zfst a + zfst 0 = zfst a |
5 |
|
addeq2 |
zfst 0 = 0 -> zfst a + zfst 0 = zfst a + 0 |
6 |
|
zfst0 |
zfst 0 = 0 |
7 |
5, 6 |
ax_mp |
zfst a + zfst 0 = zfst a + 0 |
8 |
4, 7 |
ax_mp |
zfst a + 0 = zfst a -> zfst a + zfst 0 = zfst a |
9 |
|
add0 |
zfst a + 0 = zfst a |
10 |
8, 9 |
ax_mp |
zfst a + zfst 0 = zfst a |
11 |
3, 10 |
ax_mp |
zsnd a + zsnd 0 = zsnd a -> a +Z 0 = zfst a -ZN zsnd a |
12 |
|
eqtr |
zsnd a + zsnd 0 = zsnd a + 0 -> zsnd a + 0 = zsnd a -> zsnd a + zsnd 0 = zsnd a |
13 |
|
addeq2 |
zsnd 0 = 0 -> zsnd a + zsnd 0 = zsnd a + 0 |
14 |
|
zsnd0 |
zsnd 0 = 0 |
15 |
13, 14 |
ax_mp |
zsnd a + zsnd 0 = zsnd a + 0 |
16 |
12, 15 |
ax_mp |
zsnd a + 0 = zsnd a -> zsnd a + zsnd 0 = zsnd a |
17 |
|
add0 |
zsnd a + 0 = zsnd a |
18 |
16, 17 |
ax_mp |
zsnd a + zsnd 0 = zsnd a |
19 |
11, 18 |
ax_mp |
a +Z 0 = zfst a -ZN zsnd a |
20 |
1, 19 |
ax_mp |
zfst a -ZN zsnd a = a -> a +Z 0 = a |
21 |
|
zfstsnd |
zfst a -ZN zsnd a = a |
22 |
20, 21 |
ax_mp |
a +Z 0 = a |
Axiom use
axs_prop_calc
(ax_1,
ax_2,
ax_3,
ax_mp,
itru),
axs_pred_calc
(ax_gen,
ax_4,
ax_5,
ax_6,
ax_7,
ax_10,
ax_11,
ax_12),
axs_set
(elab,
ax_8),
axs_the
(theid,
the0),
axs_peano
(peano1,
peano2,
peano5,
addeq,
muleq,
add0,
addS,
mul0,
mulS)