document.write( "Question 309970: I need help to find the product of each pair of conjugates.\r
\n" ); document.write( "\n" ); document.write( "(2sqrt3 - sqrt7)(2sqrt3 + sqrt7)
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Algebra.Com's Answer #221706 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
If we let \"x=2%2Asqrt%283%29\" and \"y=sqrt%287%29\" we get the expression \"%28x-y%29%28x%2By%29\". FOILing this expression gives us \"%28x-y%29%28x%2By%29=x%5E2-y%5E2\" which is a difference of squares. Plug \"x=2%2Asqrt%283%29\" and \"y=sqrt%287%29\" back in to get \r
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\n" ); document.write( "\n" ); document.write( "Now just multiply out and simplify the right side to get: \r
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\n" ); document.write( "\n" ); document.write( "\"%282%2Asqrt%283%29-sqrt%287%29%29%282%2Asqrt%283%29%2Bsqrt%287%29%29=4%2A3-7\" \r
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\n" ); document.write( "\n" ); document.write( "and do a bit more arithmetic to get\r
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\n" ); document.write( "\n" ); document.write( "\"%282%2Asqrt%283%29-sqrt%287%29%29%282%2Asqrt%283%29%2Bsqrt%287%29%29=5\"
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