Definition df-q 10029

Description: Define the set of rational numbers. Based on definition of rationals in [Apostol] p. 22. See elq 10031 for the relation "is rational". (Contributed by NM, 8-Jan-2002.)

Assertion

Ref	Expression
df-q	|- QQ = ( / " ( ZZ X. NN ) )

Detailed syntax breakdown of Definition df-q

Step	Hyp	Ref	Expression
1		cq 10028	. 2 class QQ
2		cdiv 9004	. . 3 class /
3		cz 9648	. . . 4 class ZZ
4		cn 9306	. . . 4 class NN
5	3, 4	cxp 4772	. . 3 class ( ZZ X. NN )
6	2, 5	cima 4777	. 2 class ( / " ( ZZ X. NN ) )
7	1, 6	wceq 1402	1 wff QQ = ( / " ( ZZ X. NN ) )

This definition is used by:  elq  10031  qnnen  13371