document.write( "Question 1089048: for what value of a does the quadratic function f(x)=ax^2-6x+3 have no
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Algebra.Com's Answer #703379 by ikleyn(52781) $\"\"$ $\"About$

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document.write( "The necessary and sufficient condition for it is that the discriminant of the equation must be negative:\r\n" );
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document.write( "d =  < 0, i.e.\r\n" );
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document.write( "(-6)^2 - 4*a*3 < 0,\r\n" );
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document.write( "36 < 12a,\r\n" );
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document.write( "a > 3.\r\n" );
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\n" ); document.write( "\n" ); document.write( "Plot y1 = $\"2x%5E2+-+6x+%2B3\"$ (red), y2 = $\"3x%5E2+-+6x+%2B3\"$ (green), y3 = $\"4x%5E2+-+6x+%2B3\"$ (blue)\r
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