Metamath Proof Explorer


Definition df-ltpq

Description: Define pre-ordering relation on positive fractions. This is a "temporary" set used in the construction of complex numbers df-c , and is intended to be used only by the construction. Similar to Definition 5 of Suppes p. 162. (Contributed by NM, 28-Aug-1995) (New usage is discouraged.)

Ref Expression
Assertion df-ltpq <pQ = { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝑥 ∈ ( N × N ) ∧ 𝑦 ∈ ( N × N ) ) ∧ ( ( 1st𝑥 ) ·N ( 2nd𝑦 ) ) <N ( ( 1st𝑦 ) ·N ( 2nd𝑥 ) ) ) }

Detailed syntax breakdown

Step Hyp Ref Expression
0 cltpq <pQ
1 vx 𝑥
2 vy 𝑦
3 1 cv 𝑥
4 cnpi N
5 4 4 cxp ( N × N )
6 3 5 wcel 𝑥 ∈ ( N × N )
7 2 cv 𝑦
8 7 5 wcel 𝑦 ∈ ( N × N )
9 6 8 wa ( 𝑥 ∈ ( N × N ) ∧ 𝑦 ∈ ( N × N ) )
10 c1st 1st
11 3 10 cfv ( 1st𝑥 )
12 cmi ·N
13 c2nd 2nd
14 7 13 cfv ( 2nd𝑦 )
15 11 14 12 co ( ( 1st𝑥 ) ·N ( 2nd𝑦 ) )
16 clti <N
17 7 10 cfv ( 1st𝑦 )
18 3 13 cfv ( 2nd𝑥 )
19 17 18 12 co ( ( 1st𝑦 ) ·N ( 2nd𝑥 ) )
20 15 19 16 wbr ( ( 1st𝑥 ) ·N ( 2nd𝑦 ) ) <N ( ( 1st𝑦 ) ·N ( 2nd𝑥 ) )
21 9 20 wa ( ( 𝑥 ∈ ( N × N ) ∧ 𝑦 ∈ ( N × N ) ) ∧ ( ( 1st𝑥 ) ·N ( 2nd𝑦 ) ) <N ( ( 1st𝑦 ) ·N ( 2nd𝑥 ) ) )
22 21 1 2 copab { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝑥 ∈ ( N × N ) ∧ 𝑦 ∈ ( N × N ) ) ∧ ( ( 1st𝑥 ) ·N ( 2nd𝑦 ) ) <N ( ( 1st𝑦 ) ·N ( 2nd𝑥 ) ) ) }
23 0 22 wceq <pQ = { ⟨ 𝑥 , 𝑦 ⟩ ∣ ( ( 𝑥 ∈ ( N × N ) ∧ 𝑦 ∈ ( N × N ) ) ∧ ( ( 1st𝑥 ) ·N ( 2nd𝑦 ) ) <N ( ( 1st𝑦 ) ·N ( 2nd𝑥 ) ) ) }