document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=251757>Question 251757</A>: <I><SPAN STYLE=\"word-break: break-all;\"> What is the proof for<BR>\n" );
document.write( "((P&#8594;Q)&#8594;Q)&#8594;(P&#8744;Q)  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #183979 by </B><A HREF=/tutors/aboutme.mpl?userid=drk><B>drk(1908)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=drk><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=183979\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> To solve this you may need a tautology table, or memorize it.\r<BR>\n" );
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document.write( "P big space Q big space P->Q big space PvQ<BR>\n" );
document.write( "T big space T big space     T      big space    T<BR>\n" );
document.write( "T big space F big space     F      big space    T<BR>\n" );
document.write( "F big space T big space     T      big space    T<BR>\n" );
document.write( "F big space F big space     T      big space    F\r<BR>\n" );
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document.write( "Now, P->Q  {T, F, T, T}\r<BR>\n" );
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document.write( "(P->Q) -> Q {T, T, T, F}\r<BR>\n" );
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document.write( "(P->Q) -> Q -> (PvQ) { T, T, T, T}\r<BR>\n" );
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document.write( "A bit tough to follow I think, but there it is. </SPAN>\n" );
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