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Metamath Proof Explorer
Theorem 0qs
Description: Quotient set with the empty set. (Contributed by Peter Mazsa, 14-Sep-2019)
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|
Ref |
Expression |
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Assertion |
0qs |
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Proof
| Step |
Hyp |
Ref |
Expression |
| 1 |
|
df-qs |
|
| 2 |
|
rex0 |
|
| 3 |
2
|
abf |
|
| 4 |
1 3
|
eqtri |
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