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 ) ) |