Theorem an12 561

Description: Swap two conjuncts. Note that the first digit (1) in the label refers to the outer conjunct position, and the next digit (2) to the inner conjunct position. (Contributed by NM, 12-Mar-1995.)

Assertion

Ref	Expression
an12	⊢ ((𝜑 ∧ (𝜓 ∧ 𝜒)) ↔ (𝜓 ∧ (𝜑 ∧ 𝜒)))

Proof of Theorem an12

Step	Hyp	Ref	Expression
1		ancom 266	. . 3 ⊢ ((𝜑 ∧ 𝜓) ↔ (𝜓 ∧ 𝜑))
2	1	anbi1i 458	. 2 ⊢ (((𝜑 ∧ 𝜓) ∧ 𝜒) ↔ ((𝜓 ∧ 𝜑) ∧ 𝜒))
3		anass 401	. 2 ⊢ (((𝜑 ∧ 𝜓) ∧ 𝜒) ↔ (𝜑 ∧ (𝜓 ∧ 𝜒)))
4		anass 401	. 2 ⊢ (((𝜓 ∧ 𝜑) ∧ 𝜒) ↔ (𝜓 ∧ (𝜑 ∧ 𝜒)))
5	2, 3, 4	3bitr3i 210	1 ⊢ ((𝜑 ∧ (𝜓 ∧ 𝜒)) ↔ (𝜓 ∧ (𝜑 ∧ 𝜒)))

Syntax hints:   ∧ wa 104   ↔ wb 105

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108

This theorem depends on definitions:  df-bi 117

This theorem is referenced by:  an32  562  an13  563  an12s  565  an4  586  ceqsrexv  2890  rmoan  2960  2reuswapdc  2964  reuind  2965  2rmorex  2966  sbccomlem  3060  elunirab  3848  rexxfrd  4494  opeliunxp  4714  elres  4978  resoprab  6014  ov6g  6056  opabex3d  6173  opabex3  6174  xpassen  6884  distrnqg  7447  distrnq0  7519  rexuz2  9646  2clim  11444  issubrg  13717  isbasis2g  14213  tgval2  14219