document.write( "Question 1081854: Given the polynomial f(x)= x^4 -6x^3 +9x^2 +4x -12 ,\r
\n" ); document.write( "\n" ); document.write( "(I) factorize f(x) completely and hence find the x and y axes intercepts\r
\n" ); document.write( "\n" ); document.write( "(II) state the x coordinates where the graph of y=f(x) cuts the x-axis and where it touches the x-axis\r
\n" ); document.write( "\n" ); document.write( "(III) draw a sign diagram for f(x)\r
\n" ); document.write( "\n" ); document.write( "(IV) discuss the behaviour of f(x) as x = ∞ and as x = -∞\r
\n" ); document.write( "\n" ); document.write( "(V) sketch the graph of y=f(x), using the information obtained above.
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Algebra.Com's Answer #695899 by josgarithmetic(39627)\"\" \"About 
You can put this solution on YOUR website!
Possible roots to try would be -6,-4,-3,-2,-1,1,2,3,4,6,12 (Rational Roots Theorem).\r
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document.write( "2   |    1   -6   9   4    -12\r\n" );
document.write( "    |         2   -8  2     12\r\n" );
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document.write( "        1    -4   1   6     0\r\n" );
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document.write( "3   |    1    -4    1     6\r\n" );
document.write( "    |\r\n" );
document.write( "    |          3    -3    -6\r\n" );
document.write( "    |______________________________\r\n" );
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document.write( "         1    -1   -2     0\r\n" );
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\n" ); document.write( "\n" ); document.write( "Partial factorizing gives \"f%28x%29=%28x-2%29%28x-3%29%28x%5E2-x-2%29\".\r
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\n" ); document.write( "\n" ); document.write( "The quadratic factor breaks into f being
\n" ); document.write( "\"f%28x%29=%28x-2%29%28x-3%29%28x-2%29%28x%2B1%29\"
\n" ); document.write( "\"highlight%28f%28x%29=%28x%2B1%29%28x-2%29%5E2%2A%28x-3%29%29\"\r
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\n" ); document.write( "\n" ); document.write( "x-intercepts:
\n" ); document.write( "-1, 2, 3\r
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\n" ); document.write( "\n" ); document.write( "y-intercept:
\n" ); document.write( "When x=0, y=-12.\r
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\n" ); document.write( "\n" ); document.write( "Table of Signs:
\n" ); document.write( "Check inside each interval on x.
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\n" ); document.write( "[-1, 2]
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\n" ); document.write( "[3, infinity)
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\n" ); document.write( "You can determine the result in each interval on your own.\r
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\n" ); document.write( "\n" ); document.write( "\"graph%28400%2C400%2C-5%2C5%2C-5%2C5%2Cx%5E4-6x%5E3%2B9x%5E2%2B4x-12%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"graph%28400%2C400%2C-3%2C4%2C-5%2C5%2Cx%5E4-6x%5E3%2B9x%5E2%2B4x-12%29\"\r
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\n" ); document.write( "\n" ); document.write( "\"graph%28400%2C400%2C-12%2C12%2C-12%2C12%2Cx%5E4-6x%5E3%2B9x%5E2%2B4x-12%29\"
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