Axiom ax-precex 7921

Description: Existence of reciprocal of positive real number. Axiom for real and complex numbers, justified by Theorem axprecex 7879. (Contributed by Jim Kingdon, 6-Feb-2020.)

Assertion

Ref	Expression
ax-precex	|- ( ( A e. RR /\ 0 <RR A ) -> E. x e. RR ( 0 <RR x /\ ( A x. x ) = 1 ) )

Distinct variable group:   x, A

Detailed syntax breakdown of Axiom ax-precex

Step	Hyp	Ref	Expression
1		cA	. . . 4 class A
2		cr 7810	. . . 4 class RR
3	1, 2	wcel 2148	. . 3 wff A e. RR
4		cc0 7811	. . . 4 class 0
5		cltrr 7815	. . . 4 class <RR
6	4, 1, 5	wbr 4004	. . 3 wff 0 <RR A
7	3, 6	wa 104	. 2 wff ( A e. RR /\ 0 <RR A )
8		vx	. . . . . 6 setvar x
9	8	cv 1352	. . . . 5 class x
10	4, 9, 5	wbr 4004	. . . 4 wff 0 <RR x
11		cmul 7816	. . . . . 6 class x.
12	1, 9, 11	co 5875	. . . . 5 class ( A x. x )
13		c1 7812	. . . . 5 class 1
14	12, 13	wceq 1353	. . . 4 wff ( A x. x ) = 1
15	10, 14	wa 104	. . 3 wff ( 0 <RR x /\ ( A x. x ) = 1 )
16	15, 8, 2	wrex 2456	. 2 wff E. x e. RR ( 0 <RR x /\ ( A x. x ) = 1 )
17	7, 16	wi 4	1 wff ( ( A e. RR /\ 0 <RR A ) -> E. x e. RR ( 0 <RR x /\ ( A x. x ) = 1 ) )

This axiom is referenced by:  recexre  8535  recexgt0  8537