Metamath Proof Explorer


Theorem 3halfnz

Description: Three halves is not an integer. (Contributed by AV, 2-Jun-2020)

Ref Expression
Assertion 3halfnz ⊢ ¬ 3 2 ∈ ℤ

Proof

Step Hyp Ref Expression
1 1z ⊢ 1 ∈ ℤ
2 2cn ⊢ 2 ∈ ℂ
3 2 mullidi ⊢ 1 ⋅ 2 = 2
4 2lt3 ⊢ 2 < 3
5 3 4 eqbrtri ⊢ 1 ⋅ 2 < 3
6 1re ⊢ 1 ∈ ℝ
7 3re ⊢ 3 ∈ ℝ
8 2re ⊢ 2 ∈ ℝ
9 2pos ⊢ 0 < 2
10 8 9 pm3.2i ⊢ 2 ∈ ℝ ∧ 0 < 2
11 ltmuldiv ⊢ 1 ∈ ℝ ∧ 3 ∈ ℝ ∧ 2 ∈ ℝ ∧ 0 < 2 → 1 ⋅ 2 < 3 ↔ 1 < 3 2
12 6 7 10 11 mp3an ⊢ 1 ⋅ 2 < 3 ↔ 1 < 3 2
13 5 12 mpbi ⊢ 1 < 3 2
14 3lt4 ⊢ 3 < 4
15 2t2e4 ⊢ 2 ⋅ 2 = 4
16 15 breq2i ⊢ 3 < 2 ⋅ 2 ↔ 3 < 4
17 14 16 mpbir ⊢ 3 < 2 ⋅ 2
18 1p1e2 ⊢ 1 + 1 = 2
19 18 breq2i ⊢ 3 2 < 1 + 1 ↔ 3 2 < 2
20 ltdivmul ⊢ 3 ∈ ℝ ∧ 2 ∈ ℝ ∧ 2 ∈ ℝ ∧ 0 < 2 → 3 2 < 2 ↔ 3 < 2 ⋅ 2
21 7 8 10 20 mp3an ⊢ 3 2 < 2 ↔ 3 < 2 ⋅ 2
22 19 21 bitri ⊢ 3 2 < 1 + 1 ↔ 3 < 2 ⋅ 2
23 17 22 mpbir ⊢ 3 2 < 1 + 1
24 btwnnz ⊢ 1 ∈ ℤ ∧ 1 < 3 2 ∧ 3 2 < 1 + 1 → ¬ 3 2 ∈ ℤ
25 1 13 23 24 mp3an ⊢ ¬ 3 2 ∈ ℤ