document.write( "Question 930626: Write the equation, in standard form, of a polynomial with real coefficients that has roots at 2, 1−2i, and 1+4i, and passes through the point (0,98). \r
\n" ); document.write( "\n" ); document.write( "Your answer should include only (decimal) numbers, the letter \"x\", and the characters \"+\", \"-\", and \"^\" \r
\n" ); document.write( "\n" ); document.write( "f(x)=___________
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Algebra.Com's Answer #565186 by MathLover1(20849)\"\" \"About 
You can put this solution on YOUR website!
Write the equation, in standard form, of a polynomial with real coefficients that has roots at :\r
\n" ); document.write( "\n" ); document.write( "\"2\",
\n" ); document.write( "\"1-2i\", complex roots always come in pairs, so you have \"1%2B2i\" too
\n" ); document.write( "\"1%2B4i\", and \"1-4i\" as well\r
\n" ); document.write( "\n" ); document.write( "passes through the point (\"0\",\"98\"). \r
\n" ); document.write( "\n" ); document.write( " where \"a\" is coefficient\r
\n" ); document.write( "\n" ); document.write( "\"f%28x%29=a%28x%5E5-6x%5E4%2B34x%5E3-96x%5E2%2B173x-170%29\"\r
\n" ); document.write( "\n" ); document.write( "since passes through the point (\"0\",\"98\") set \"f%28x%29=98\" and \"x=0\" and solve for coefficient \"a\"\r
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\n" ); document.write( "\n" ); document.write( "\"98=a%280%5E5-6%2A0%5E4%2B34%2A0%5E3-96%2A0%5E2%2B173%2A0-170%29\"\r
\n" ); document.write( "\n" ); document.write( "\"98=a%28-170%29\"\r
\n" ); document.write( "\n" ); document.write( "\"a=98%2F%28-170%29\"\r
\n" ); document.write( "\n" ); document.write( "\"a=-0.5764705882352941\" exact value, and for more accurate result I will use exact value\r
\n" ); document.write( "\n" ); document.write( "\"f%28x%29=-0.5764705882352941%28x%5E5-6x%5E4%2B34x%5E3-96x%5E2%2B173x-170%29\"\r
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\n" ); document.write( "\n" ); document.write( "we can round it and get shorter form, but zeros will not be exact\r
\n" ); document.write( "\n" ); document.write( "\"f%28x%29=-0.58x%5E5%2B3.46x%5E4-19.6x%5E3%2B55.34x%5E2-99.7x%2B98\"\r
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