Metamath Proof Explorer


Theorem nnssi2

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 )

Proof

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 )