Description: The predicate "is an even number". An even number is an integer which is divisible by 2. (Contributed by AV, 18-Jun-2020)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | iseven2 | ⊢ ( 𝑍 ∈ Even ↔ ( 𝑍 ∈ ℤ ∧ 2 ∥ 𝑍 ) ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | breq2 | ⊢ ( 𝑧 = 𝑍 → ( 2 ∥ 𝑧 ↔ 2 ∥ 𝑍 ) ) | |
| 2 | dfeven2 | ⊢ Even = { 𝑧 ∈ ℤ ∣ 2 ∥ 𝑧 } | |
| 3 | 1 2 | elrab2 | ⊢ ( 𝑍 ∈ Even ↔ ( 𝑍 ∈ ℤ ∧ 2 ∥ 𝑍 ) ) |