document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1026781>Question 1026781</A>: <I><SPAN STYLE=\"word-break: break-all;\"> I am trying to solve this proof:<BR>\n" );
document.write( "premises: A or B, A or C\r<BR>\n" );
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document.write( "goal: A or (B and C) \r<BR>\n" );
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document.write( "I know that I need to use subproofs to solve this, but I don't know how far I need to break down each premise with a subproof to solve this. <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 #642185 by </B><A HREF=/tutors/aboutme.mpl?userid=richard1234><B>richard1234(7193)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richard1234><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/cgi-bin/show-face.mpl?user=richard1234><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=642185\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Do casework based on whether A is true or not.\r<BR>\n" );
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document.write( "Case 1: A is true. Then the premise is already satisfied, and so is the goal.\r<BR>\n" );
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document.write( "Case 2: A is false. Since (A or B) is true, and (A or C) is true, it follows for the premise to hold, B must be true, and C must be true. Then (B and C) follows. </SPAN>\n" );
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