document.write( "Question 1149079: use an ordinary proof (not conditional or indirect proof) \r
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Algebra.Com's Answer #770590 by math_helper(2461) $\"\"$ $\"About$

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document.write( "1. F⊃(J∨∼F)      Premise     	 
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document.write( "2. J⊃(L∨∼J)	 Premise
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document.write( "// Show F⊃L\r
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document.write( "3. ~Fv(Jv~F)     1, Material Implication (MI)
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document.write( "4. ~FvJ          3, IdemV Elimination (may go by other names, AvBvA == AvB)
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document.write( "5.  F⊃J          4, MI
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document.write( "6.  ~Jv(Lv~J)    2, MI
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document.write( "7.  ~JvL         6, IdemV Elimination 
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document.write( "8.  J⊃L          7, MI
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document.write( "9.  F⊃L          5,8 Hypothetical Syllogism (HS)\r
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document.write( "*** Proof complete ***
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