document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=252410>Question 252410</A>: <I><SPAN STYLE=\"word-break: break-all;\"> What are the other roots of <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y=x%5E3-6x%5E2%2B13x-20 ALIGN=MIDDLE  ALT=\"y=x%5E3-6x%5E2%2B13x-20\"   DISABLED_style= \"max-width:90%; height:auto;\" > if one of its roots is 1+2i </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #184304 by </B><A HREF=/tutors/aboutme.mpl?userid=drk><B>drk(1908)</B></A><img src=\"/images/stars/stars-12.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=drk><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=184304\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Since 1 + 2i is a root its conjugate 1 - 2i is also a root. Conjugates always travel in pairs. So [x-1+2i][x-1-2i] = X^2 -2x + 5 appears to be a root. By polynomial division, we get x-4.\r<BR>\n" );
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document.write( "SO, the three roots are X = 1+-2i, 4. </SPAN>\n" );
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