document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=968367>Question 968367</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Find the solution to the polynomial inequality  x^3+5x^2-4x-20>0\r<BR>\n" );
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document.write( "thanks:) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #591746 by </B><A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><B>josgarithmetic(39618)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=josgarithmetic><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=591746\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Roots are -5, -2, 2.  That much you would find using Rational Roots Theorem and synthetic division.\r<BR>\n" );
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document.write( "You can test the intervals, but you could also make use of characteristic knowledge of how the shapes of cubic functions are.  Cubic, degree 3; two humps; function rises from the far left and rises to the far right.  You KNOW the inequality is false to the left of -5, and you KNOW the inequality is true to the right of 2.\r<BR>\n" );
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document.write( "Figure on the rest.\r<BR>\n" );
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document.write( "Unsure of the inequality but found roots on your own:\r<BR>\n" );
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document.write( "Test a value inside each interval.  Which intervals have values which satisfy the inequality, and which intervals do not satisfy the inequality?\r<BR>\n" );
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document.write( "The roots found cut the x-axis into specific intervals:<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-infinity%3Cx%3C-5 ALIGN=MIDDLE  ALT=\"-infinity%3Cx%3C-5\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-5%3Cx%3C-2 ALIGN=MIDDLE  ALT=\"-5%3Cx%3C-2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=-2%3Cx%3C2 ALIGN=MIDDLE  ALT=\"-2%3Cx%3C2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=2%3Cx%3Cinfinity ALIGN=MIDDLE  ALT=\"2%3Cx%3Cinfinity\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "Literally pick a value in each interval and test to see if it makes the inequality true.\r<BR>\n" );
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document.write( "Another tutor showed the final answer.  That answer is correct. </SPAN>\n" );
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