SOLUTION: D→(B→C), B & −C ├ −D

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Question 978496: D→(B→C), B & −C ├ −D
Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
 1.  D→(B→C)   premise
 2.  B&~C      premise
       conclusion: ├ ~D

 3.  (D&B)→C,    1, Importation
 4.  ~C→~(D&B)   3, Contrapositive
 5.  ~C          2, Simplification
 6.  ~(D&B)      4,5, Modus Ponens
 7.  ~Dv~B       6, DeMorgan's Law
 8.  B           2, Simplification
 9.  ~~B         8, Double Negation
10.  ~D          7,9, Disjunctive Syllogism 
 
Edwin