document.write( "Question 1132145: In the equation 2x^2 — 3x + 4 = 0, what is the sum of the squares of the roots? \n" ); document.write( "

Algebra.Com's Answer #749064 by ikleyn(52778) $\"\"$ $\"About$

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document.write( "Let \"a\" and \"b\" be the roots.\r\n" );
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document.write( "Then, according to Vieta's theorem\r\n" );
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document.write( "    a + b = ,     (1)\r\n" );
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document.write( "    ab =  = 2.    (2)\r\n" );
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document.write( "Now,   =  - 2ab =  - 2*2 =  = .     ANSWER\r\n" );
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\n" ); document.write( "\n" ); document.write( "Solved.\r
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\n" ); document.write( "\n" ); document.write( "By the way, since the sum of squares is negative (as you see from the answer),\r
\n" ); document.write( "\n" ); document.write( "it means that the roots are COMPLEX NUMBERS.\r
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\n" ); document.write( "\n" ); document.write( "The lesson to learn from the solution is THIS :\r
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document.write( "    You do not need to find the roots of the equation explicitly to answer the question.\r\n" );
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\n" ); document.write( "\n" ); document.write( "So, my solution saved you from making tons of non-necessary calculations.\r
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