Theorem nnaddcld 8938

Description: Closure of addition of positive integers. (Contributed by Mario Carneiro, 27-May-2016.)

Hypotheses

Ref	Expression
nnge1d.1	⊢ (𝜑 → 𝐴 ∈ ℕ)
nnmulcld.2	⊢ (𝜑 → 𝐵 ∈ ℕ)

Assertion

Ref	Expression
nnaddcld	⊢ (𝜑 → (𝐴 + 𝐵) ∈ ℕ)

Proof of Theorem nnaddcld

Step	Hyp	Ref	Expression
1		nnge1d.1	. 2 ⊢ (𝜑 → 𝐴 ∈ ℕ)
2		nnmulcld.2	. 2 ⊢ (𝜑 → 𝐵 ∈ ℕ)
3		nnaddcl 8910	. 2 ⊢ ((𝐴 ∈ ℕ ∧ 𝐵 ∈ ℕ) → (𝐴 + 𝐵) ∈ ℕ)
4	1, 2, 3	syl2anc 411	1 ⊢ (𝜑 → (𝐴 + 𝐵) ∈ ℕ)

Syntax hints:   → wi 4   ∈ wcel 2146  (class class class)co 5865   + caddc 7789  ℕcn 8890

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 709  ax-5 1445  ax-7 1446  ax-gen 1447  ax-ie1 1491  ax-ie2 1492  ax-8 1502  ax-10 1503  ax-11 1504  ax-i12 1505  ax-bndl 1507  ax-4 1508  ax-17 1524  ax-i9 1528  ax-ial 1532  ax-i5r 1533  ax-ext 2157  ax-sep 4116  ax-cnex 7877  ax-resscn 7878  ax-1cn 7879  ax-1re 7880  ax-addrcl 7883  ax-addass 7888

This theorem depends on definitions:  df-bi 117  df-3an 980  df-tru 1356  df-nf 1459  df-sb 1761  df-clab 2162  df-cleq 2168  df-clel 2171  df-nfc 2306  df-ral 2458  df-rex 2459  df-rab 2462  df-v 2737  df-un 3131  df-in 3133  df-ss 3140  df-sn 3595  df-pr 3596  df-op 3598  df-uni 3806  df-int 3841  df-br 3999  df-iota 5170  df-fv 5216  df-ov 5868  df-inn 8891

This theorem is referenced by:  pythagtriplem4  12233  pythagtriplem6  12235  pythagtriplem7  12236  pythagtriplem11  12239  pythagtriplem12  12240  pythagtriplem13  12241  pythagtriplem14  12242  pythagtriplem15  12243  pythagtriplem16  12244  mulgnndir  12870