Step | Hyp | Ref | Expression |
1 |
|
muleq2 |
x = b -> suc a * x = suc a * b |
2 |
|
muleq2 |
x = b -> a * x = a * b |
3 |
|
id |
x = b -> x = b |
4 |
2, 3 |
addeqd |
x = b -> a * x + x = a * b + b |
5 |
1, 4 |
eqeqd |
x = b -> (suc a * x = a * x + x <-> suc a * b = a * b + b) |
6 |
|
muleq2 |
x = 0 -> suc a * x = suc a * 0 |
7 |
|
muleq2 |
x = 0 -> a * x = a * 0 |
8 |
|
id |
x = 0 -> x = 0 |
9 |
7, 8 |
addeqd |
x = 0 -> a * x + x = a * 0 + 0 |
10 |
6, 9 |
eqeqd |
x = 0 -> (suc a * x = a * x + x <-> suc a * 0 = a * 0 + 0) |
11 |
|
muleq2 |
x = y -> suc a * x = suc a * y |
12 |
|
muleq2 |
x = y -> a * x = a * y |
13 |
|
id |
x = y -> x = y |
14 |
12, 13 |
addeqd |
x = y -> a * x + x = a * y + y |
15 |
11, 14 |
eqeqd |
x = y -> (suc a * x = a * x + x <-> suc a * y = a * y + y) |
16 |
|
muleq2 |
x = suc y -> suc a * x = suc a * suc y |
17 |
|
muleq2 |
x = suc y -> a * x = a * suc y |
18 |
|
id |
x = suc y -> x = suc y |
19 |
17, 18 |
addeqd |
x = suc y -> a * x + x = a * suc y + suc y |
20 |
16, 19 |
eqeqd |
x = suc y -> (suc a * x = a * x + x <-> suc a * suc y = a * suc y + suc y) |
21 |
|
eqtr4 |
suc a * 0 = 0 -> a * 0 + 0 = 0 -> suc a * 0 = a * 0 + 0 |
22 |
|
mul0 |
suc a * 0 = 0 |
23 |
21, 22 |
ax_mp |
a * 0 + 0 = 0 -> suc a * 0 = a * 0 + 0 |
24 |
|
eqtr |
a * 0 + 0 = a * 0 -> a * 0 = 0 -> a * 0 + 0 = 0 |
25 |
|
add0 |
a * 0 + 0 = a * 0 |
26 |
24, 25 |
ax_mp |
a * 0 = 0 -> a * 0 + 0 = 0 |
27 |
|
mul0 |
a * 0 = 0 |
28 |
26, 27 |
ax_mp |
a * 0 + 0 = 0 |
29 |
23, 28 |
ax_mp |
suc a * 0 = a * 0 + 0 |
30 |
|
mulS |
suc a * suc y = suc a * y + suc a |
31 |
|
eqtr |
a * suc y + suc y = a * y + a + suc y -> a * y + a + suc y = a * y + y + suc a -> a * suc y + suc y = a * y + y + suc a |
32 |
|
addeq1 |
a * suc y = a * y + a -> a * suc y + suc y = a * y + a + suc y |
33 |
|
mulS |
a * suc y = a * y + a |
34 |
32, 33 |
ax_mp |
a * suc y + suc y = a * y + a + suc y |
35 |
31, 34 |
ax_mp |
a * y + a + suc y = a * y + y + suc a -> a * suc y + suc y = a * y + y + suc a |
36 |
|
eqtr |
a * y + a + suc y = suc (a * y + a + y) -> suc (a * y + a + y) = a * y + y + suc a -> a * y + a + suc y = a * y + y + suc a |
37 |
|
addS |
a * y + a + suc y = suc (a * y + a + y) |
38 |
36, 37 |
ax_mp |
suc (a * y + a + y) = a * y + y + suc a -> a * y + a + suc y = a * y + y + suc a |
39 |
|
eqtr4 |
suc (a * y + a + y) = suc (a * y + y + a) -> a * y + y + suc a = suc (a * y + y + a) -> suc (a * y + a + y) = a * y + y + suc a |
40 |
|
suceq |
a * y + a + y = a * y + y + a -> suc (a * y + a + y) = suc (a * y + y + a) |
41 |
|
addrass |
a * y + a + y = a * y + y + a |
42 |
40, 41 |
ax_mp |
suc (a * y + a + y) = suc (a * y + y + a) |
43 |
39, 42 |
ax_mp |
a * y + y + suc a = suc (a * y + y + a) -> suc (a * y + a + y) = a * y + y + suc a |
44 |
|
addS |
a * y + y + suc a = suc (a * y + y + a) |
45 |
43, 44 |
ax_mp |
suc (a * y + a + y) = a * y + y + suc a |
46 |
38, 45 |
ax_mp |
a * y + a + suc y = a * y + y + suc a |
47 |
35, 46 |
ax_mp |
a * suc y + suc y = a * y + y + suc a |
48 |
|
addeq1 |
suc a * y = a * y + y -> suc a * y + suc a = a * y + y + suc a |
49 |
30, 47, 48 |
eqtr4g |
suc a * y = a * y + y -> suc a * suc y = a * suc y + suc y |
50 |
5, 10, 15, 20, 29, 49 |
ind |
suc a * b = a * b + b |