Description: A virtual deduction elimination rule. (Contributed by Alan Sare, 12-Jun-2011) (Proof modification is discouraged.) (New usage is discouraged.)
Ref | Expression | ||
---|---|---|---|
Hypotheses | e123.1 | |
|
e123.2 | |
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e123.3 | |
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e123.4 | |
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Assertion | e123 | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | e123.1 | |
|
2 | e123.2 | |
|
3 | e123.3 | |
|
4 | e123.4 | |
|
5 | 1 | vd13 | |
6 | 2 | vd23 | |
7 | 5 6 3 4 | e333 | |