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Theorem biraldv2 1221
Description: Formula-building rule for restricted universal quantifier (deduction rule).
Hypothesis
Ref Expression
biraldv2.1 (φ → ((xAψ) ↔ (xBχ)))
Assertion
Ref Expression
biraldv2 (φ → (∀xA ψ ↔ ∀xB χ))
Distinct variable group(s):   φ,x

Proof of Theorem biraldv2
StepHypRef Expression
1 biraldv2.1 . . 3 (φ → ((xAψ) ↔ (xBχ)))
21bialdv 935 . 2 (φ → (∀x(xAψ) ↔ ∀x(xBχ)))
3 df-ral 1205 . 2 (∀xA ψ ↔ ∀x(xAψ))
4 df-ral 1205 . 2 (∀xB χ ↔ ∀x(xBχ))
52, 3, 43bitr4g 428 1 (φ → (∀xA ψ ↔ ∀xB χ))
Colors of variables: wff set class
Syntax hints:   → wi 2   ↔ wb 127  ∀wal 672   ∈ wcel 1092  ∀wral 1201
This theorem is referenced by:  oneqmini 2272  zornlem1 3603  iscard2 3660
This theorem was proved from axioms:  ax-1 3  ax-2 4  ax-3 5  ax-mp 6  ax-4 673  ax-5 674  ax-gen 677  ax-17 925
This theorem depends on definitions:  df-bi 128  df-an 198  df-ral 1205
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