document.write( "Question 705705: If the roots of 2x^2 +3x-1=0 are alpha and beta. Find the values of alpha square + beta square \n" ); document.write( "
Algebra.Com's Answer #434730 by KMST(5328)\"\" \"About 
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If the roots of \"2x%5E2+%2B3x-1=0\" are \"alpha\" and \"beta\", then
\n" ); document.write( "\"alpha%2Bbeta=-3%2F2\" and
\n" ); document.write( "\"%28alpha%29%28beta%29=-1%2F2\"
\n" ); document.write( "(Reasons below)
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\n" ); document.write( "Then \"alpha%5E2%2Bbeta%5E2\" can be easily calculated as:
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\n" ); document.write( "\"alpha%5E2%2Bbeta%5E2=%28-3%2F2%29%5E2-2%28-1%2F2%29\"
\n" ); document.write( "\"alpha%5E2%2Bbeta%5E2=9%2F4%2B1\"
\n" ); document.write( "\"highlight%28alpha%5E2%2Bbeta%5E2=13%2F4%29\" or \"highlight%28alpha%5E2%2Bbeta%5E2=3%261%2F4%29\" or \"highlight%28alpha%5E2%2Bbeta%5E2=3.25%29\"
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\n" ); document.write( "REASONS:
\n" ); document.write( "The sum of the solutions to the quadratic equation \"ax%5E2%2Bbx%2Bc=0\" equals \"-b%2Fa\"
\n" ); document.write( "and the product equals \"c%2Fa\" .
\n" ); document.write( "Why?
\n" ); document.write( "Because if roots of \"2x%5E2+%2B3x-1=0\" are \"alpha\" and \"beta\",
\n" ); document.write( "factoring should transform that equation into
\n" ); document.write( "\"a%28x-alpha%29%28x-beta%29=0\" --> \"a%28x%5E2-beta%2Ax-alpha%2Ax%2B%28alpha%29%28beta%29%29=0\" --> \"a%28x%5E2-%28beta%2Balpha%29%2Ax%2B%28alpha%29%28beta%29%29=0\" --> \"ax%5E2-a%28beta%2Balpha%29%2Ax%2Ba%28alpha%29%28beta%29=0\"
\n" ); document.write( "and if that equation must be equivalent to \"ax%5E2%2Bbx%2Bc=0\",
\n" ); document.write( "all three coefficients must be the same.
\n" ); document.write( "The coefficient of the term in \"x\" is
\n" ); document.write( "\"b=-a%28beta%2Balpha%29\" --> \"-b%2Fa=beta%2Balpha\".
\n" ); document.write( "The constant (or independent term) is
\n" ); document.write( "\"c=a%28alpha%29%28beta%29\" --> \"c%2Fa=%28alpha%29%28beta%29\"
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