document.write( "Question 1207167: Hi, can you please help me with this question:
\n" ); document.write( "C-(B union A') for a three way venn diagram
\n" ); document.write( "I keep confusing myself and get stuck.
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Algebra.Com's Answer #844889 by ikleyn(52781) $\"\"$ $\"About$

You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( " In the post by Edwin, his final answer C-(B U A') = (g,j) is INCORRECT.\r
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\n" ); document.write( "\n" ); document.write( " The correct answer is C-(B U A') = (g).\r
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document.write( "Indeed, at an informal level, you should subtract/remove from C all its parts that \r\n" );
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document.write( "        - do belong to B, i.e. h and i;\r\n" );
document.write( "    and \r\n" );
document.write( "        - do not belong to A, i.e. j.\r\n" );
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document.write( "So, what remains of C is g.  At the informal level, at this point the solution is complete.\r\n" );
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document.write( "At a formal level, there are several errors in the Edwin's post.\r\n" );
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document.write( "First, objects/subsets \"a\", \"b\", \"c\" should not present in the lists, because THERE ARE NOT such subsets;\r\n" );
document.write( "there are A, B and C, but we should not list them, since they are replaced by smaller subsets.\r\n" );
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document.write( "Second, this line in the Edwin's post is incorrect\r\n" );
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document.write( "    (e,f,h,i) U (a,b,c,f,i,j,k) means all of those regions, (a,b,c,e,f,h,i,k).\r\n" );
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document.write( "The correct form for this line is \r\n" );
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document.write( "    (e,f,h,i) U (f,i,j,k) means all of those regions, (e,f,h,i,j,k).\r\n" );
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document.write( "In this line, \"j\" was missed by Edwin, which led him to wrong answer later.\r\n" );
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\n" ); document.write( "\n" ); document.write( "In general, playing with Venn diagrams always recalls me transferring matches
\n" ); document.write( "from one matchbox to another.
\n" ); document.write( "This produces an impression that a person is busy with something,
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\n" ); document.write( "what develops a person's mind.\r
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\n" ); document.write( "\n" ); document.write( "Only illusions of learning . . . \r
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