Metamath Proof Explorer


Theorem 3halfnz

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

Ref Expression
Assertion 3halfnz ¬ 3 2

Proof

Step Hyp Ref Expression
1 1z 1
2 2cn 2
3 2 mulid2i 1 2 = 2
4 2lt3 2 < 3
5 3 4 eqbrtri 1 2 < 3
6 1re 1
7 3re 3
8 2re 2
9 2pos 0 < 2
10 8 9 pm3.2i 2 0 < 2
11 ltmuldiv 1 3 2 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 2 2 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 1 < 3 2 3 2 < 1 + 1 ¬ 3 2
25 1 13 23 24 mp3an ¬ 3 2