document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=707955>Question 707955</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I have been wrestling with trying to solve this proof.....Pleeaaassseee HELP!<BR>\n" );
document.write( "(J->L)->(M->N),A,A->(J->L),(M->N)->[(J->L)->O],O->(A->B)|-B\r<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #435925 by </B><A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><B>jim_thompson5910(35256)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=jim_thompson5910><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=435925\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> You have A (ie you're assuming A is true) and you have this\r<BR>\n" );
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document.write( "A -> (J -> L)\r<BR>\n" );
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document.write( "So you can use modus ponens to get J -> L\r<BR>\n" );
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document.write( "You have this statement\r<BR>\n" );
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document.write( "(J->L)->(M->N)\r<BR>\n" );
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document.write( "and you can use modus ponens with this and the \"J -> L\" you got earlier to get M -> N\r<BR>\n" );
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document.write( "Now you have M -> N and (M->N)->[(J->L)->O]\r<BR>\n" );
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document.write( "Use modus ponens to get (J->L)->O\r<BR>\n" );
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document.write( "Then use modus ponens again with J -> L and (J->L)->O to get O\r<BR>\n" );
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document.write( "You now have O and O -> (A -> B)\r<BR>\n" );
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document.write( "Use modus ponens to get A -> B\r<BR>\n" );
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document.write( "Finally, use modus ponens with A and A -> B to get B\r<BR>\n" );
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document.write( "So all of the given statements and using modus ponens a bunch of times leads us to the conclusion of B\r<BR>\n" );
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document.write( "This proves that the argument and conclusion is valid. </SPAN>\n" );
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