Metamath Proof Explorer
Description: Class substitution into a membership relation. (Contributed by NM, 17-Nov-2006) (Proof shortened by Andrew Salmon, 29-Jun-2011)
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Ref |
Expression |
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Assertion |
sbcel2gv |
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Proof
Step |
Hyp |
Ref |
Expression |
1 |
|
eleq2 |
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2 |
|
eleq2 |
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3 |
1 2
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sbcie2g |
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