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Description: If the function value for a given argument is not empty, the argument belongs to the support of the function with the empty set as zero. (Contributed by AV, 2-Jul-2019) (Revised by AV, 4-Apr-2020)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | fvn0elsupp |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | simpr | ||
| 2 | simpr | ||
| 3 | 1 2 | anim12i | |
| 4 | simprl | ||
| 5 | simpll | ||
| 6 | 0ex | ||
| 7 | 6 | a1i | |
| 8 | elsuppfn | ||
| 9 | 4 5 7 8 | syl3anc | |
| 10 | 3 9 | mpbird |