document.write( "Question 1081854: Given the polynomial f(x)= x^4 -6x^3 +9x^2 +4x -12 ,\r
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document.write( "(I) factorize f(x) completely and hence find the x and y axes intercepts\r
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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
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document.write( "(III) draw a sign diagram for f(x)\r
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document.write( "(IV) discuss the behaviour of f(x) as x = ∞ and as x = -∞\r
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document.write( "(V) sketch the graph of y=f(x), using the information obtained above. \n" );
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Algebra.Com's Answer #695899 by josgarithmetic(39627) ![]() 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 \n" ); document.write( "\n" ); document.write( " \r\n" ); document.write( "2 | 1 -6 9 4 -12\r\n" ); document.write( " | 2 -8 2 12\r\n" ); document.write( " |________________________________\r\n" ); document.write( " 1 -4 1 6 0\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "3 | 1 -4 1 6\r\n" ); document.write( " |\r\n" ); document.write( " | 3 -3 -6\r\n" ); document.write( " |______________________________\r\n" ); document.write( "\r\n" ); document.write( " 1 -1 -2 0\r\n" ); document.write( "\r\n" ); document.write( "\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Partial factorizing gives \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "The quadratic factor breaks into f being \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "x-intercepts: \n" ); document.write( "-1, 2, 3\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "y-intercept: \n" ); document.write( "When x=0, y=-12.\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Table of Signs: \n" ); document.write( "Check inside each interval on x. \n" ); document.write( "- \n" ); document.write( "(infin, -1] \n" ); document.write( "[-1, 2] \n" ); document.write( "[2, 3] \n" ); document.write( "[3, infinity) \n" ); document.write( "- \n" ); document.write( "You can determine the result in each interval on your own.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " |