or42 - Intuitionistic Logic Explorer

	Intuitionistic Logic Explorer		< Previous Next > Nearby theorems
Mirrors > Home > ILE Home > Th. List > or42		Unicode version

Theorem or42 689

Description: Rearrangement of 4 disjuncts. (Contributed by NM, 10-Jan-2005.)

**Assertion**
Ref	Expression
or42	$\/$ $\/$ $\/$ $\/$ $\/$ $\/$

**Proof of Theorem or42**
Step	Hyp	Ref	Expression
1		or4 688	. 2 $\/$ $\/$ $\/$ $\/$ $\/$ $\/$
2		orcom 647	. . 3 $\/$ $\/$
3	2	orbi2i 679	. 2 $\/$ $\/$ $\/$ $\/$ $\/$ $\/$
4	1, 3	bitri 173	1 $\/$ $\/$ $\/$ $\/$ $\/$ $\/$

Colors of variables: wff set class

Syntax hints:

wb 98 $\/$ wo 629

This theorem was proved from axioms: ax-1 5 ax-2 6 ax-mp 7 ax-ia1 99 ax-ia2 100 ax-ia3 101 ax-io 630

This theorem depends on definitions: df-bi 110

This theorem is referenced by: reapcotr 7589