document.write( "Question 392539: Factor the following and list all the zeros (roots):\r
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document.write( "x^3+4x^2-4x-16 \n" );
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Algebra.Com's Answer #278610 by haileytucki(390)![]() ![]() You can put this solution on YOUR website! x^(3)+4x^(2)-4x-16\r \n" ); document.write( "\n" ); document.write( "If a polynomial function has integer coefficients, then every rational zero will have the form (p)/(q) where p is a factor of the constant and q is a factor of the leading coefficient. \n" ); document.write( "p=16_q=1\r \n" ); document.write( "\n" ); document.write( "Find every combination of \(p)/(q). These are the possible roots of the polynomial function. \n" ); document.write( "+-1,+-2,+-4,+-8,+-16\r \n" ); document.write( "\n" ); document.write( "Substitute the possible roots one by one into the polynomial to find the actual roots. Simplify to check if the value is 0, which means it is a root. \n" ); document.write( "(2)^(3)+4(2)^(2)-4(2)-16\r \n" ); document.write( "\n" ); document.write( "Simplify the expression. In this case, the expression is equal to 0 so x=2 is a root of the polynomial. \n" ); document.write( "0\r \n" ); document.write( "\n" ); document.write( "Since 2 is a known root, divide the polynomial by (x-2) to find the quotient polynomial. This polynomial can then be used to find the remaining roots. \n" ); document.write( "(x^(3)+4x^(2)-4x-16)/(x-2)\r \n" ); document.write( "\n" ); document.write( "Complete the synthetic division of ((x^(3)+4x^(2)-4x-16))/((x-2)). \n" ); document.write( "2,1,4,-4,-16:1,1,2,12,16:1,1,6,8,0\r \n" ); document.write( "\n" ); document.write( "Next, find the roots of the remaining polynomial. The order of the polynomial has been reduced by 1. \n" ); document.write( "x^(2)+6x+8\r \n" ); document.write( "\n" ); document.write( "Solve the equation to find any remaining roots. \n" ); document.write( "x=-4,-2\r \n" ); document.write( "\n" ); document.write( "The polynomial can be written as a set of linear factors. \n" ); document.write( "(x-2)(x+4)(x+2)\r \n" ); document.write( "\n" ); document.write( "These are the roots (i.e. zeros) of the polynomial x^(3)+4x^(2)-4x-16. \n" ); document.write( "x=2,-4,-2 \n" ); document.write( " |