Theorem rexbii2 3108

Description: Inference adding different restricted existential quantifiers to each side of an equivalence. (Contributed by NM, 4-Feb-2004.)

Hypothesis

Ref	Expression
rexbii2.1	⊢ ((𝑥 ∈ 𝐴 ∧ 𝜑) ↔ (𝑥 ∈ 𝐵 ∧ 𝜓))

Assertion

Ref	Expression
rexbii2	⊢ (∃𝑥 ∈ 𝐴 𝜑 ↔ ∃𝑥 ∈ 𝐵 𝜓)

Proof of Theorem rexbii2

Step	Hyp	Ref	Expression
1		rexbii2.1	. . 3 ⊢ ((𝑥 ∈ 𝐴 ∧ 𝜑) ↔ (𝑥 ∈ 𝐵 ∧ 𝜓))
2	1	exbii 1871	. 2 ⊢ (∃𝑥(𝑥 ∈ 𝐴 ∧ 𝜑) ↔ ∃𝑥(𝑥 ∈ 𝐵 ∧ 𝜓))
3		df-rex 3090	. 2 ⊢ (∃𝑥 ∈ 𝐴 𝜑 ↔ ∃𝑥(𝑥 ∈ 𝐴 ∧ 𝜑))
4		df-rex 3090	. 2 ⊢ (∃𝑥 ∈ 𝐵 𝜓 ↔ ∃𝑥(𝑥 ∈ 𝐵 ∧ 𝜓))
5	2, 3, 4	3bitr4i 306	1 ⊢ (∃𝑥 ∈ 𝐴 𝜑 ↔ ∃𝑥 ∈ 𝐵 𝜓)

Syntax hints:   ↔ wb 209   ∧ wa 400  ∃wex 1802   ∈ wcel 2145  ∃wrex 3089

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1818  ax-4 1832

This theorem depends on definitions:  df-bi 210  df-ex 1803  df-rex 3090

This theorem is referenced by:  rexbiia  3110  rexeqbii  3338  rexrab  3662  rexin  4205  rexdifpr  4621  rexdifsn  4757  reusv2lem4  5362  reusv2  5364  frpoind  6332  eldifsucnn  8638  frind  9710  rexuz2  12911  rexrp  13027  rexuz3  15388  infpn2  16961  efgrelexlemb  19808  cmpcov2  23504  cmpfi  23522  txkgen  23766  cubic  26968  madeval2  27980  sumdmdii  32672  extdgfialglem1  33994  bnj882  35226  bnj893  35228  heibor1  38316  eldmqsres  38799  prtlem100  39490  islmodfg  43653  iuneq1i  45663  limcrecl  46204