SOLUTION: use an ordinary proof (not conditional or indirect proof) 1. F⊃(J∨∼F) 2. J⊃(L∨∼J) / F⊃L

Algebra ->  Proofs -> SOLUTION: use an ordinary proof (not conditional or indirect proof) 1. F⊃(J∨∼F) 2. J⊃(L∨∼J) / F⊃L       Log On


   

Question 1149079: use an ordinary proof (not conditional or indirect proof)
1. F⊃(J∨∼F)
2. J⊃(L∨∼J) / F⊃L
Answer by math_helper(2461) About Me  (Show Source):
You can put this solution on YOUR website!


1. F⊃(J∨∼F)      Premise     	 

2. J⊃(L∨∼J)	 Premise

// Show F⊃L



3. ~Fv(Jv~F)     1, Material Implication (MI)

4. ~FvJ          3, IdemV Elimination (may go by other names, AvBvA == AvB)

5.  F⊃J          4, MI

6.  ~Jv(Lv~J)    2, MI

7.  ~JvL         6, IdemV Elimination 

8.  J⊃L          7, MI

9.  F⊃L          5,8 Hypothetical Syllogism (HS)



*** Proof complete ***