Definition df-rmo 2530

Description: Define restricted "at most one". (Contributed by NM, 16-Jun-2017.)

Assertion

Ref	Expression
df-rmo	⊢ (∃*𝑥 ∈ 𝐴 𝜑 ↔ ∃*𝑥(𝑥 ∈ 𝐴 ∧ 𝜑))

Detailed syntax breakdown of Definition df-rmo

Step	Hyp	Ref	Expression
1		wph	. . 3 wff 𝜑
2		vx	. . 3 setvar 𝑥
3		cA	. . 3 class 𝐴
4	1, 2, 3	wrmo 2525	. 2 wff ∃*𝑥 ∈ 𝐴 𝜑
5	2	cv 1397	. . . . 5 class 𝑥
6	5, 3	wcel 2205	. . . 4 wff 𝑥 ∈ 𝐴
7	6, 1	wa 104	. . 3 wff (𝑥 ∈ 𝐴 ∧ 𝜑)
8	7, 2	wmo 2083	. 2 wff ∃*𝑥(𝑥 ∈ 𝐴 ∧ 𝜑)
9	4, 8	wb 105	1 wff (∃*𝑥 ∈ 𝐴 𝜑 ↔ ∃*𝑥(𝑥 ∈ 𝐴 ∧ 𝜑))

This definition is referenced by:  nfrmo1  2718  cbvrmow  2729  rmobida  2734  rmobiia  2737  rmoeq1f  2742  mormo  2763  reu5  2764  rmo5  2767  rmov  2836  rmo4  3013  rmo3f  3017  rmoan  3020  rmoim  3021  rmoimi2  3023  2reuswapdc  3024  2rmorex  3026  rmo2ilem  3136  rmo3  3138  rmob  3139  ssrmof  3305  dfdisj2  4092  dffun9  5386  fncnv  5427