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Mirrors > Home > MPE Home > Th. List > df-ss | Structured version Visualization version Unicode version |
Description: Define the subclass
relationship. Exercise 9 of [TakeutiZaring] p. 18.
For example, ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() ![]() |
Ref | Expression |
---|---|
df-ss |
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Step | Hyp | Ref | Expression |
---|---|---|---|
1 | cA |
. . 3
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2 | cB |
. . 3
![]() ![]() | |
3 | 1, 2 | wss 3416 |
. 2
![]() ![]() ![]() ![]() |
4 | 1, 2 | cin 3415 |
. . 3
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5 | 4, 1 | wceq 1455 |
. 2
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6 | 3, 5 | wb 189 |
1
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