Question 1104540
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1.	N &#8835; (F • A)	
2.	B &#8835; (R • F)	/ (N &#8744; B) &#8835; (A &#8744; R)

                  | 3.  N &#8744; B                      ACP
                  | 4.  (F • A) &#8744; (R • F)   1,2,3, constructive dilemma CD
                  | 5.  (F • A) &#8744; (F • R)       4, commutation
                  | 6.  F • (A &#8744; R)             5, distribution
                  | 7.  (A &#8744; R) • F             6, commutation
                  | 8.  A &#8744; R                   7, simplification
9.    (N &#8744; B) &#8835; (A &#8744; R)                    3-8    CP      

Edwin</pre>