Definition df-nr

Description: Define class of signed reals. This is a "temporary" set used in the construction of complex numbers df-c , and is intended to be used only by the construction. From Proposition 9-4.2 of Gleason p. 126. (Contributed by NM, 25-Jul-1995) (New usage is discouraged.)

	Ref	Expression
Assertion	df-nr	$$⊢𝑹=\left(𝑷\times 𝑷\right)/{~}_{𝑹}$$

Detailed syntax breakdown

Step	Hyp	Ref	Expression
0		cnr	$$class𝑹$$
1		cnp	$$class𝑷$$
2	1 1	cxp	$$class\left(𝑷\times 𝑷\right)$$
3		cer	$$class{~}_{𝑹}$$
4	2 3	cqs	$$class\left(\left(𝑷\times 𝑷\right)/{~}_{𝑹}\right)$$
5	0 4	wceq	$$wff𝑹=\left(𝑷\times 𝑷\right)/{~}_{𝑹}$$