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 = ÷ ×

Detailed syntax breakdown

Step Hyp Ref Expression
0 cq class
1 cdiv class ÷
2 cz class
3 cn class
4 2 3 cxp class ×
5 1 4 cima class ÷ ×
6 0 5 wceq wff = ÷ ×