document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=128923>Question 128923</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the roots<BR>\n" );
document.write( "X^3 - X^2 + 15X - 17 = 0\r<BR>\n" );
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document.write( "If I use synthetic division, I get<BR>\n" );
document.write( "(X + 1)(X^2 - 2x + 17)\r<BR>\n" );
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document.write( "This is where I am stuck. I need help to finish it because I can't get synthetic division to come out right.\r<BR>\n" );
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document.write( "Thank you.<BR>\n" );
document.write( "Laura </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #94286 by </B><A HREF=/tutors/aboutme.mpl?userid=oscargut><B>oscargut(2103)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=oscargut><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/cgi-bin/show-face.mpl?user=oscargut><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=94286\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> maybe you wrote wrong X^3 - X^2 + 15X - 17 = 0<BR>\n" );
document.write( "i think is X^3 - X^2 + 15X +17 = 0\r<BR>\n" );
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document.write( "a simple root is x=-1  so doing the synthetic division  \r<BR>\n" );
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document.write( "   1  -1   15    17<BR>\n" );
document.write( "-1    -1    2   -17<BR>\n" );
document.write( "   1  -2   17    0\r<BR>\n" );
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document.write( "and then your result is valid X^3 - X^2 + 15X +17 =(X + 1)(X^2 - 2x + 17)\r<BR>\n" );
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document.write( "then you have to solve X^2 - 2x + 17=0 but the roots of this function are not real because (-2)^2-4(1)(17)=-64<0 then the only real root is -1\r<BR>\n" );
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document.write( "and the others are  (2+sqrt(-64))/2 and (2-sqrt(-64))/2\r<BR>\n" );
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document.write( "so in complex notation  1+4i  and  1-4i \r<BR>\n" );
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document.write( "Then R: -1,1+4i,1-4i<BR>\n" );
document.write( " </SPAN>\n" );
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