document.write( "Question 459087: Let A and B be subsets of U={a,b,c,d,1,2,3,4} A={a,2}
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Algebra.Com's Answer #314891 by Edwin McCravy(20086)\"\" \"About 
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Let A and B be subsets of U={a,b,c,d,1,2,3,4} A={a,2}
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document.write( "First draw a big rectangle for the universal set U:\r\n" );
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document.write( "Next draw a circle and label it A:\r\n" );
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document.write( "Next draw a circle overlapping the first circle and\r\n" );
document.write( "label it B. \r\n" );
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document.write( "The overlapping part is the set A ∩ B which is given\r\n" );
document.write( "to be {2}.\r\n" );
document.write( "So we put \"2\" in the overlapping part, the sort \r\n" );
document.write( "of football-shaped area in the middle, shaped sort \r\n" );
document.write( "of like this: \"()\".\r\n" );
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document.write( "Now we are told that A={a,2}. A is the entire \r\n" );
document.write( "left circle.  Since we already have the \"2\" as\r\n" );
document.write( "the only element of A ∩ B, then the \"a\" must go\r\n" );
document.write( "in the leftmost part of circle A, which is sort of a \r\n" );
document.write( "moon-shaped region part of the circle    \r\n" );
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document.write( "We are told that A ∪ B = {a,c,d,2,4} which is the\r\n" );
document.write( "whole figure 8 part, consisting of both circles\r\n" );
document.write( "together, and \"2\" is the only element in the \"()\" part,\r\n" );
document.write( "and a is the only element in the left \"moon\" part.\r\n" );
document.write( "so all the rest of the elements of A ∪ B must go in the \r\n" );
document.write( "right part of B, the moon-shaped part of the \r\n" );
document.write( "circle on the far right, so we will put the other elements \r\n" );
document.write( "of A ∪ B, which are \"c\", \"d\", and \"4\", over there, like \r\n" );
document.write( "this:\r\n" );
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document.write( "We can stop there because we have placed all the\r\n" );
document.write( "elements in both sets A and B.  B consists of\r\n" );
document.write( "all the elements in the right circle, so the\r\n" );
document.write( "answer is B = {c,d,2,4}\r\n" );
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document.write( "However let's finish the Venn diagram. All the rest\r\n" );
document.write( "of the elements \"b\",\"1\",and \"3\" of the universal \r\n" );
document.write( "set U go outside of both circles, so we will put\r\n" );
document.write( "them outside the circles: \r\n" );
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document.write( "Edwin
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