Theorem nnaddcld 8901

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 8873	. 2 ⊢ ((𝐴 ∈ ℕ ∧ 𝐵 ∈ ℕ) → (𝐴 + 𝐵) ∈ ℕ)
4	1, 2, 3	syl2anc 409	1 ⊢ (𝜑 → (𝐴 + 𝐵) ∈ ℕ)

Syntax hints:   → wi 4   ∈ wcel 2136  (class class class)co 5841   + caddc 7752  ℕcn 8853

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 699  ax-5 1435  ax-7 1436  ax-gen 1437  ax-ie1 1481  ax-ie2 1482  ax-8 1492  ax-10 1493  ax-11 1494  ax-i12 1495  ax-bndl 1497  ax-4 1498  ax-17 1514  ax-i9 1518  ax-ial 1522  ax-i5r 1523  ax-ext 2147  ax-sep 4099  ax-cnex 7840  ax-resscn 7841  ax-1cn 7842  ax-1re 7843  ax-addrcl 7846  ax-addass 7851

This theorem depends on definitions:  df-bi 116  df-3an 970  df-tru 1346  df-nf 1449  df-sb 1751  df-clab 2152  df-cleq 2158  df-clel 2161  df-nfc 2296  df-ral 2448  df-rex 2449  df-rab 2452  df-v 2727  df-un 3119  df-in 3121  df-ss 3128  df-sn 3581  df-pr 3582  df-op 3584  df-uni 3789  df-int 3824  df-br 3982  df-iota 5152  df-fv 5195  df-ov 5844  df-inn 8854

This theorem is referenced by:  pythagtriplem4  12196  pythagtriplem6  12198  pythagtriplem7  12199  pythagtriplem11  12202  pythagtriplem12  12203  pythagtriplem13  12204  pythagtriplem14  12205  pythagtriplem15  12206  pythagtriplem16  12207