Description: Convert a theorem for real/complex numbers into one for positive integers. (Contributed by Jeff Hoffman, 17-Jun-2008)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | nnssi2.1 | |- NN C_ D | |
| nnssi2.2 | |- ( B e. NN -> ph ) | ||
| nnssi2.3 | |- ( ( A e. D /\ B e. D /\ ph ) -> ps ) | ||
| Assertion | nnssi2 | |- ( ( A e. NN /\ B e. NN ) -> ps ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | nnssi2.1 | |- NN C_ D | |
| 2 | nnssi2.2 | |- ( B e. NN -> ph ) | |
| 3 | nnssi2.3 | |- ( ( A e. D /\ B e. D /\ ph ) -> ps ) | |
| 4 | 1 | sseli | |- ( A e. NN -> A e. D ) | 
| 5 | 1 | sseli | |- ( B e. NN -> B e. D ) | 
| 6 | 4 5 2 | 3anim123i | |- ( ( A e. NN /\ B e. NN /\ B e. NN ) -> ( A e. D /\ B e. D /\ ph ) ) | 
| 7 | 6 | 3anidm23 | |- ( ( A e. NN /\ B e. NN ) -> ( A e. D /\ B e. D /\ ph ) ) | 
| 8 | 7 3 | syl | |- ( ( A e. NN /\ B e. NN ) -> ps ) |