Metamath Proof Explorer


Definition df-1p

Description: Define the positive real constant 1. This is a "temporary" set used in the construction of complex numbers df-c , and is intended to be used only by the construction. Definition of Gleason p. 122. (Contributed by NM, 13-Mar-1996) (New usage is discouraged.)

Ref Expression
Assertion df-1p 1𝑷=x|x<𝑸1𝑸

Detailed syntax breakdown

Step Hyp Ref Expression
0 c1p class1𝑷
1 vx setvarx
2 1 cv setvarx
3 cltq class<𝑸
4 c1q class1𝑸
5 2 4 3 wbr wffx<𝑸1𝑸
6 5 1 cab classx|x<𝑸1𝑸
7 0 6 wceq wff1𝑷=x|x<𝑸1𝑸