ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  sbanv GIF version

Theorem sbanv 1936
Description: Version of sban 2006 where 𝑥 and 𝑦 are distinct. (Contributed by Jim Kingdon, 24-Dec-2017.)
Assertion
Ref Expression
sbanv ([𝑦 / 𝑥](𝜑𝜓) ↔ ([𝑦 / 𝑥]𝜑 ∧ [𝑦 / 𝑥]𝜓))
Distinct variable group:   𝑥,𝑦
Allowed substitution hints:   𝜑(𝑥,𝑦)   𝜓(𝑥,𝑦)

Proof of Theorem sbanv
StepHypRef Expression
1 sb6 1933 . 2 ([𝑦 / 𝑥](𝜑𝜓) ↔ ∀𝑥(𝑥 = 𝑦 → (𝜑𝜓)))
2 sb6 1933 . . . 4 ([𝑦 / 𝑥]𝜑 ↔ ∀𝑥(𝑥 = 𝑦𝜑))
3 sb6 1933 . . . 4 ([𝑦 / 𝑥]𝜓 ↔ ∀𝑥(𝑥 = 𝑦𝜓))
42, 3anbi12i 460 . . 3 (([𝑦 / 𝑥]𝜑 ∧ [𝑦 / 𝑥]𝜓) ↔ (∀𝑥(𝑥 = 𝑦𝜑) ∧ ∀𝑥(𝑥 = 𝑦𝜓)))
5 19.26 1527 . . 3 (∀𝑥((𝑥 = 𝑦𝜑) ∧ (𝑥 = 𝑦𝜓)) ↔ (∀𝑥(𝑥 = 𝑦𝜑) ∧ ∀𝑥(𝑥 = 𝑦𝜓)))
6 pm4.76 606 . . . 4 (((𝑥 = 𝑦𝜑) ∧ (𝑥 = 𝑦𝜓)) ↔ (𝑥 = 𝑦 → (𝜑𝜓)))
76albii 1516 . . 3 (∀𝑥((𝑥 = 𝑦𝜑) ∧ (𝑥 = 𝑦𝜓)) ↔ ∀𝑥(𝑥 = 𝑦 → (𝜑𝜓)))
84, 5, 73bitr2i 208 . 2 (([𝑦 / 𝑥]𝜑 ∧ [𝑦 / 𝑥]𝜓) ↔ ∀𝑥(𝑥 = 𝑦 → (𝜑𝜓)))
91, 8bitr4i 187 1 ([𝑦 / 𝑥](𝜑𝜓) ↔ ([𝑦 / 𝑥]𝜑 ∧ [𝑦 / 𝑥]𝜓))
Colors of variables: wff set class
Syntax hints:  wi 4  wa 104  wb 105  wal 1393  [wsb 1808
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-5 1493  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-11 1552  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580
This theorem depends on definitions:  df-bi 117  df-sb 1809
This theorem is referenced by:  sban  2006
  Copyright terms: Public domain W3C validator