document.write( "Question 1136706: Find the values for a for which the graph y=a^2x^2-2ax-a+1
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Algebra.Com's Answer #754508 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
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\n" ); document.write( "\n" ); document.write( "\"y=a%5E2x%5E2-2ax-a%2B1\"\r
\n" ); document.write( "\n" ); document.write( "1) crosses the x-axis
\n" ); document.write( "2) does not cross the x-axis \r
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\n" ); document.write( "\n" ); document.write( "use discriminant D=b^2-4ac\r
\n" ); document.write( "\n" ); document.write( "if \"D%3E0\" we have \"two\"\"+distinct\"\"+real\" zeros
\n" ); document.write( "if \"D%3C0\" we have \"two\" \"complex\" zeros\r
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\n" ); document.write( "\n" ); document.write( "\"D=%282a%29%5E2-4a%5E2%2A%28-a%2B1%29\"\r
\n" ); document.write( "\n" ); document.write( "\"D=4a%5E2%2B4a%5E3%2B4\"\r
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\n" ); document.write( "\n" ); document.write( "find\r
\n" ); document.write( "\n" ); document.write( "\"4a%5E3%2B4a%5E2%2B4%3E0\"..simplify\r
\n" ); document.write( "\n" ); document.write( "\"a%5E3%2Ba%5E2%2B1%3E0\"-> put it in calculator and you will get \r
\n" ); document.write( "\n" ); document.write( "\"a%3E-1.46557\"\r
\n" ); document.write( "\n" ); document.write( "now try with \"a=1\" which is greater then \"-1.46557\"\r
\n" ); document.write( "\n" ); document.write( "\"y=1%5E2x%5E2-2%2A1%2Ax-1%2B1\"\r
\n" ); document.write( "\n" ); document.write( "\"y=x%5E2-2x\"\r
\n" ); document.write( "\n" ); document.write( "find x-intercepts:\r
\n" ); document.write( "\n" ); document.write( "\"x%5E2-2x=0\"\r
\n" ); document.write( "\n" ); document.write( "\"%28x-2%29x=0\"\r
\n" ); document.write( "\n" ); document.write( "=>\"x=0\" or \"x=2\"\r
\n" ); document.write( "\n" ); document.write( "check the graph to see x-intercepts\r
\n" ); document.write( "\n" ); document.write( "\"+graph%28+600%2C+600%2C+-10%2C10%2C+-10%2C+10%2C+x%5E2-2x%29+\"\r
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\n" ); document.write( "\n" ); document.write( "and\r
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\n" ); document.write( "\n" ); document.write( "if \"D%3C0\" we have two \"complex\" zeros; means there are no x-intercepts\r
\n" ); document.write( "\n" ); document.write( "\"a%3C-1.46557\"\r
\n" ); document.write( "\n" ); document.write( "choose any value of \"a\" greater than \"-1.46557\": try with \"a=-1\"\r
\n" ); document.write( "\n" ); document.write( "\"y=%28-1%29%5E2x%5E2-2%2A%28-1%29%2Ax-%28-1%29%2B1\"\r
\n" ); document.write( "\n" ); document.write( "\"y=x%5E2%2B2x%2B1%2B1\"\r
\n" ); document.write( "\n" ); document.write( "\"y=x%5E2%2B2x%2B2\"\r
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\n" ); document.write( "\n" ); document.write( "\"+graph%28+600%2C+600%2C+-10%2C10%2C+-10%2C+10%2Cx%5E2%2B2x%2B2%29+\"\r
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