Theorem pm5.32 426

Description: Distribution of implication over biconditional. Theorem *5.32 of [WhiteheadRussell] p. 125. (Contributed by NM, 1-Aug-1994.) (Revised by NM, 31-Jan-2015.)

Assertion

Ref	Expression
pm5.32	⊢ ((𝜑 → (𝜓 ↔ 𝜒)) ↔ ((𝜑 ∧ 𝜓) ↔ (𝜑 ∧ 𝜒)))

Proof of Theorem pm5.32

Step	Hyp	Ref	Expression
1		id 19	. . 3 ⊢ ((𝜑 → (𝜓 ↔ 𝜒)) → (𝜑 → (𝜓 ↔ 𝜒)))
2	1	pm5.32d 423	. 2 ⊢ ((𝜑 → (𝜓 ↔ 𝜒)) → ((𝜑 ∧ 𝜓) ↔ (𝜑 ∧ 𝜒)))
3		ibar 285	. . . 4 ⊢ (𝜑 → (𝜓 ↔ (𝜑 ∧ 𝜓)))
4		ibar 285	. . . 4 ⊢ (𝜑 → (𝜒 ↔ (𝜑 ∧ 𝜒)))
5	3, 4	bibi12d 224	. . 3 ⊢ (𝜑 → ((𝜓 ↔ 𝜒) ↔ ((𝜑 ∧ 𝜓) ↔ (𝜑 ∧ 𝜒))))
6	5	biimprcd 149	. 2 ⊢ (((𝜑 ∧ 𝜓) ↔ (𝜑 ∧ 𝜒)) → (𝜑 → (𝜓 ↔ 𝜒)))
7	2, 6	impbii 117	1 ⊢ ((𝜑 → (𝜓 ↔ 𝜒)) ↔ ((𝜑 ∧ 𝜓) ↔ (𝜑 ∧ 𝜒)))

Syntax hints:   → wi 4   ∧ wa 97   ↔ wb 98

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101

This theorem depends on definitions:  df-bi 110

This theorem is referenced by:  pm5.32i  427  xordidc  1290  cbvex2  1797  rabbi  2487  rabxfrd  4201  asymref  4710  rexrnmpt  5310  mpt22eqb  5610