document.write( "Question 389113: Which of the following products is a rational number?
\n" ); document.write( "1: (2+sqrt[2])(2+sqrt[2])
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\n" ); document.write( "3: sqrt[2](2+sqrt[2])
\n" ); document.write( "4: 2(2-sqrt[2])
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Algebra.Com's Answer #275617 by richard1234(7193)\"\" \"About 
You can put this solution on YOUR website!
#2 is rational, it is a difference of two squares problem.\r
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\n" ); document.write( "\n" ); document.write( "\"%282+%2B+sqrt%282%29%29%282+-+sqrt%282%29%29+=+2%5E2+-+%28sqrt%282%29%29%5E2+=+2\"
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