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Theorem sborv 1878
Description: Version of sbor 1942 where 𝑥 and 𝑦 are distinct. (Contributed by Jim Kingdon, 3-Feb-2018.)
Assertion
Ref Expression
sborv ([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 sborv
StepHypRef Expression
1 sb5 1875 . . 3 ([𝑦 / 𝑥](𝜑𝜓) ↔ ∃𝑥(𝑥 = 𝑦 ∧ (𝜑𝜓)))
2 andi 808 . . . 4 ((𝑥 = 𝑦 ∧ (𝜑𝜓)) ↔ ((𝑥 = 𝑦𝜑) ∨ (𝑥 = 𝑦𝜓)))
32exbii 1593 . . 3 (∃𝑥(𝑥 = 𝑦 ∧ (𝜑𝜓)) ↔ ∃𝑥((𝑥 = 𝑦𝜑) ∨ (𝑥 = 𝑦𝜓)))
4 19.43 1616 . . 3 (∃𝑥((𝑥 = 𝑦𝜑) ∨ (𝑥 = 𝑦𝜓)) ↔ (∃𝑥(𝑥 = 𝑦𝜑) ∨ ∃𝑥(𝑥 = 𝑦𝜓)))
51, 3, 43bitri 205 . 2 ([𝑦 / 𝑥](𝜑𝜓) ↔ (∃𝑥(𝑥 = 𝑦𝜑) ∨ ∃𝑥(𝑥 = 𝑦𝜓)))
6 sb5 1875 . . 3 ([𝑦 / 𝑥]𝜑 ↔ ∃𝑥(𝑥 = 𝑦𝜑))
7 sb5 1875 . . 3 ([𝑦 / 𝑥]𝜓 ↔ ∃𝑥(𝑥 = 𝑦𝜓))
86, 7orbi12i 754 . 2 (([𝑦 / 𝑥]𝜑 ∨ [𝑦 / 𝑥]𝜓) ↔ (∃𝑥(𝑥 = 𝑦𝜑) ∨ ∃𝑥(𝑥 = 𝑦𝜓)))
95, 8bitr4i 186 1 ([𝑦 / 𝑥](𝜑𝜓) ↔ ([𝑦 / 𝑥]𝜑 ∨ [𝑦 / 𝑥]𝜓))
Colors of variables: wff set class
Syntax hints:  wa 103  wb 104  wo 698  wex 1480  [wsb 1750
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 699  ax-5 1435  ax-gen 1437  ax-ie1 1481  ax-ie2 1482  ax-8 1492  ax-11 1494  ax-4 1498  ax-17 1514  ax-i9 1518  ax-ial 1522
This theorem depends on definitions:  df-bi 116  df-sb 1751
This theorem is referenced by:  sbor  1942
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