document.write( "Question 215532: Solve over the set of complex numbers. Use completing the square.\r
\n" ); document.write( "\n" ); document.write( "8x^2-x-1=0 (the x on first term is squared)\r
\n" ); document.write( "\n" ); document.write( "Thank you
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Algebra.Com's Answer #162916 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
8x^2 - x - 1 = 0
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\n" ); document.write( "8x^2 - x = 1
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\n" ); document.write( "The coefficient of x^2 has to be 1, divide all terms by 8
\n" ); document.write( "x^2 - \"1%2F8\"x = \"1%2F8\"
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\n" ); document.write( "x^2 - \"1%2F8\"x + ___ = \"1%2F8\"
\n" ); document.write( "Find the 3rd term that completes the square, divide the coefficient of x by 2
\n" ); document.write( "then square it; that would be (-1/16)^2, which is \"1%2F256\", add to both sides
\n" ); document.write( "x^2 - \"1%2F8\"x + \"1%2F256\" = \"1%2F8\" + \"1%2F256\"
\n" ); document.write( "x^2 - \"1%2F8\"x + \"1%2F256\" = \"32%2F256\" + \"1%2F256\"
\n" ); document.write( "x^2 - \"1%2F8\"x + \"1%2F256\" = \"33%2F256\"
\n" ); document.write( "which is:
\n" ); document.write( "(x - \"1%2F16\")^2 = \"33%2F256\"
\n" ); document.write( "Find the square root of both sides
\n" ); document.write( "x - \"1%2F16\" = +/-\"sqrt%2833%2F256%29\"
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\n" ); document.write( "We can extract the square root of (1/256) which is 1/16
\n" ); document.write( "x - \"1%2F16\" = +/-\"%281%2F16%29sqrt%2833%29\"
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\n" ); document.write( "Add 1/16 to both sides
\n" ); document.write( "x = \"1%2F16\" +/-\"%281%2F16%29sqrt%2833%29\"
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\n" ); document.write( "From this we can write the two solutions as:
\n" ); document.write( "x = \"%281+%2B+sqrt%2833%29%29%2F16\"
\n" ); document.write( "and
\n" ); document.write( "x = \"%281+-+sqrt%2833%29%29%2F16\"
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\n" ); document.write( "Did you understand what went on here? Let me know, ankor@att.net
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