Theorem nnaddcld 8969

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 8941	. 2 ⊢ ((𝐴 ∈ ℕ ∧ 𝐵 ∈ ℕ) → (𝐴 + 𝐵) ∈ ℕ)
4	1, 2, 3	syl2anc 411	1 ⊢ (𝜑 → (𝐴 + 𝐵) ∈ ℕ)

Syntax hints:   → wi 4   ∈ wcel 2148  (class class class)co 5877   + caddc 7816  ℕcn 8921

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 1447  ax-7 1448  ax-gen 1449  ax-ie1 1493  ax-ie2 1494  ax-8 1504  ax-10 1505  ax-11 1506  ax-i12 1507  ax-bndl 1509  ax-4 1510  ax-17 1526  ax-i9 1530  ax-ial 1534  ax-i5r 1535  ax-ext 2159  ax-sep 4123  ax-cnex 7904  ax-resscn 7905  ax-1cn 7906  ax-1re 7907  ax-addrcl 7910  ax-addass 7915

This theorem depends on definitions:  df-bi 117  df-3an 980  df-tru 1356  df-nf 1461  df-sb 1763  df-clab 2164  df-cleq 2170  df-clel 2173  df-nfc 2308  df-ral 2460  df-rex 2461  df-rab 2464  df-v 2741  df-un 3135  df-in 3137  df-ss 3144  df-sn 3600  df-pr 3601  df-op 3603  df-uni 3812  df-int 3847  df-br 4006  df-iota 5180  df-fv 5226  df-ov 5880  df-inn 8922

This theorem is referenced by:  pythagtriplem4  12270  pythagtriplem6  12272  pythagtriplem7  12273  pythagtriplem11  12276  pythagtriplem12  12277  pythagtriplem13  12278  pythagtriplem14  12279  pythagtriplem15  12280  pythagtriplem16  12281  mulgnndir  13017  lgseisenlem2  14536