This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.
Metamath Proof Explorer
Description: The subtraction operation is a set. (Contributed by SN, 5-Jun-2025)
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Ref |
Expression |
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Assertion |
subex |
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Proof
| Step |
Hyp |
Ref |
Expression |
| 1 |
|
subf |
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| 2 |
|
cnex |
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| 3 |
2 2
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xpex |
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| 4 |
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fex2 |
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| 5 |
1 3 2 4
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mp3an |
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