Metamath Proof Explorer


Definition df-q

Description: Define the set of rational numbers. Based on definition of rationals in Apostol p. 22. See elq for the relation "is rational". (Contributed by NM, 8-Jan-2002)

Ref Expression
Assertion df-q ℚ = ( / “ ( ℤ × ℕ ) )

Detailed syntax breakdown

Step Hyp Ref Expression
0 cq ⊢ ℚ
1 cdiv ⊢ /
2 cz ⊢ ℤ
3 cn ⊢ ℕ
4 2 3 cxp ⊢ ( ℤ × ℕ )
5 1 4 cima ⊢ ( / “ ( ℤ × ℕ ) )
6 0 5 wceq ⊢ ℚ = ( / “ ( ℤ × ℕ ) )