document.write( "Question 1171516: Could you please help me with this problem?
\n" ); document.write( "A → B, A ⋁ C, B → D, ¬C ⊢ E ⋁ D\r
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Algebra.Com's Answer #797613 by math_helper(2461) $\"\"$ $\"About$

You can put this solution on YOUR website!


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document.write( "1. A --> B       Premise
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document.write( "2. A V C         Premise
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document.write( "3. B --> D       Premise
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document.write( "// prove this leads to ~C --> E V D\r
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document.write( "4. :: ~C             Conditional Proof (CP) assumption #1
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document.write( "5. :: A              4,2  Disjunctive Syllogism (DS)
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document.write( "6. :: B              5,1  Modus Ponens (MP)
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document.write( "7. :: D              6,3  MP
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document.write( "8. :: ~C --> D       4-7  CP
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document.write( "9. :: ~C --> D v E   8  Addition (ADD)
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document.write( "10.:: ~C --> E v D   9  Commutative Property
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document.write( "11. ~C --> E v D     4-10 CP, discharges CP assumptions\r
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