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Theorem axpowg 35787
Description: A generalization of ax-pow 5327 that combines it and zfpow 5328 into a single theorem scheme. Unlike ax-pow 5327, this scheme lacks a distinct variable condition for 𝑦 and 𝑤. (Contributed by BTernaryTau, 26-May-2026.)
Assertion
Ref Expression
axpowg ∃𝑦∀𝑧(∀𝑤(𝑤 ∈ 𝑧 → 𝑤 ∈ 𝑥) → 𝑧 ∈ 𝑦)
Distinct variable groups:   𝑥,𝑦,𝑧   𝑥,𝑤,𝑧

Proof of Theorem axpowg
Dummy variable 𝑣 is distinct from all other variables.
StepHypRef Expression
1 ax-pow 5327 . 2 ∃𝑦∀𝑧(∀𝑣(𝑣 ∈ 𝑧 → 𝑣 ∈ 𝑥) → 𝑧 ∈ 𝑦)
2 elequ1 2152 . . . . . . 7 (𝑣 = 𝑤 → (𝑣 ∈ 𝑧 ↔ 𝑤 ∈ 𝑧))
3 elequ1 2152 . . . . . . 7 (𝑣 = 𝑤 → (𝑣 ∈ 𝑥 ↔ 𝑤 ∈ 𝑥))
42, 3imbi12d 347 . . . . . 6 (𝑣 = 𝑤 → ((𝑣 ∈ 𝑧 → 𝑣 ∈ 𝑥) ↔ (𝑤 ∈ 𝑧 → 𝑤 ∈ 𝑥)))
54cbvalvw 2069 . . . . 5 (∀𝑣(𝑣 ∈ 𝑧 → 𝑣 ∈ 𝑥) ↔ ∀𝑤(𝑤 ∈ 𝑧 → 𝑤 ∈ 𝑥))
65imbi1i 352 . . . 4 ((∀𝑣(𝑣 ∈ 𝑧 → 𝑣 ∈ 𝑥) → 𝑧 ∈ 𝑦) ↔ (∀𝑤(𝑤 ∈ 𝑧 → 𝑤 ∈ 𝑥) → 𝑧 ∈ 𝑦))
76albii 1852 . . 3 (∀𝑧(∀𝑣(𝑣 ∈ 𝑧 → 𝑣 ∈ 𝑥) → 𝑧 ∈ 𝑦) ↔ ∀𝑧(∀𝑤(𝑤 ∈ 𝑧 → 𝑤 ∈ 𝑥) → 𝑧 ∈ 𝑦))
87exbii 1881 . 2 (∃𝑦∀𝑧(∀𝑣(𝑣 ∈ 𝑧 → 𝑣 ∈ 𝑥) → 𝑧 ∈ 𝑦) ↔ ∃𝑦∀𝑧(∀𝑤(𝑤 ∈ 𝑧 → 𝑤 ∈ 𝑥) → 𝑧 ∈ 𝑦))
91, 8mpbi 233 1 ∃𝑦∀𝑧(∀𝑤(𝑤 ∈ 𝑧 → 𝑤 ∈ 𝑥) → 𝑧 ∈ 𝑦)
Colors of variables:    wff setvar class
This proof depends on syntax axioms:   → wi 4  ∀wal 1568  ∃wex 1812
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2147  ax-pow 5327
This proof depends on definitions:  df-bi 210  df-an 402  df-ex 1813
This theorem is used by:  axpowg3  35789
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