Theorem iseven 42385

Description: The predicate "is an even number". An even number is an integer which is divisible by 2, i.e. the result of dividing the even integer by 2 is still an integer. (Contributed by AV, 14-Jun-2020.)

Assertion

Ref	Expression
iseven	⊢ (𝑍 ∈ Even ↔ (𝑍 ∈ ℤ ∧ (𝑍 / 2) ∈ ℤ))

Proof of Theorem iseven

Dummy variable 𝑧 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		oveq1 6917	. . 3 ⊢ (𝑧 = 𝑍 → (𝑧 / 2) = (𝑍 / 2))
2	1	eleq1d 2891	. 2 ⊢ (𝑧 = 𝑍 → ((𝑧 / 2) ∈ ℤ ↔ (𝑍 / 2) ∈ ℤ))
3		df-even 42383	. 2 ⊢ Even = {𝑧 ∈ ℤ ∣ (𝑧 / 2) ∈ ℤ}
4	2, 3	elrab2 3589	1 ⊢ (𝑍 ∈ Even ↔ (𝑍 ∈ ℤ ∧ (𝑍 / 2) ∈ ℤ))

Syntax hints:   ↔ wb 198   ∧ wa 386   = wceq 1656   ∈ wcel 2164  (class class class)co 6910   / cdiv 11016  2c2 11413  ℤcz 11711   Even ceven 42381

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1894  ax-4 1908  ax-5 2009  ax-6 2075  ax-7 2112  ax-9 2173  ax-10 2192  ax-11 2207  ax-12 2220  ax-13 2389  ax-ext 2803

This theorem depends on definitions:  df-bi 199  df-an 387  df-or 879  df-3an 1113  df-tru 1660  df-ex 1879  df-nf 1883  df-sb 2068  df-clab 2812  df-cleq 2818  df-clel 2821  df-nfc 2958  df-rex 3123  df-rab 3126  df-v 3416  df-dif 3801  df-un 3803  df-in 3805  df-ss 3812  df-nul 4147  df-if 4309  df-sn 4400  df-pr 4402  df-op 4406  df-uni 4661  df-br 4876  df-iota 6090  df-fv 6135  df-ov 6913  df-even 42383

This theorem is referenced by:  evenz  42387  evendiv2z  42389  evenm1odd  42396  evenp1odd  42397  oddp1eveni  42398  oddm1eveni  42399  evennodd  42400  oddneven  42401  enege  42402  zeoALTV  42425  oddm1evenALTV  42430  oddp1evenALTV  42431  0evenALTV  42443  2evenALTV  42447  6even  42464  8even  42466