document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=149309>Question 149309</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hi I really need some help in solving this..this is new to me.Any help will be gladly be appreciated.\r<BR>\n" );
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document.write( "how do you solve \r<BR>\n" );
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document.write( "f(x)= Xcube minus 4x squared plus 7x minus 2\r<BR>\n" );
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document.write( "f(x) = (4x - 7) to the power of 20 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #109584 by </B><A HREF=/tutors/aboutme.mpl?userid=Fombitz><B>Fombitz(32388)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Fombitz><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=Fombitz><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=109584\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> By solve, I assume you mean find the zeros where f(x)=0.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=f%28x%29=x%5E3-4x%5E2%2B7x-2 ALIGN=MIDDLE  ALT=\"f%28x%29=x%5E3-4x%5E2%2B7x-2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Typically the easiest way is to graph and look for the function crossing the x axis.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+graph%28+300%2C+300%2C+-20%2C+20%0D%0A%2C+-10%2C+10%2C+x%5E3-4x%5E2%2B7x-2%29+ ALIGN=MIDDLE  ALT=\"+graph%28+300%2C+300%2C+-20%2C+20%0D%0A%2C+-10%2C+10%2C+x%5E3-4x%5E2%2B7x-2%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Looks like it crosses once at about x=1/3.<BR>\n" );
document.write( "Since there are three roots for a cubic equation, the other two roots are complex.<BR>\n" );
document.write( "Using Excel to window down the real solution gives x=0.349370808.<BR>\n" );
document.write( "That gives a value of f(x)=-2.6e-9. That's pretty close to zero.<BR>\n" );
document.write( "The other two roots are complex.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=1.82531+%2B-+1.5468689i ALIGN=MIDDLE  ALT=\"x=1.82531+%2B-+1.5468689i\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "There is an explanation of how to find zeros for a cubic equation at http://www.1728.com/cubic.htm.\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+graph%28+300%2C+300%2C+-1%2C+2%0D%0A%2C+-10%2C+10%2C+x%5E3-4x%5E2%2B7x-2%29+ ALIGN=MIDDLE  ALT=\"+graph%28+300%2C+300%2C+-1%2C+2%0D%0A%2C+-10%2C+10%2C+x%5E3-4x%5E2%2B7x-2%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
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document.write( "The other function is simpler.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=f%28x%29=%284x-7%29%5E20 ALIGN=MIDDLE  ALT=\"f%28x%29=%284x-7%29%5E20\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "This equals zero when <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%284x-7%29=0 ALIGN=MIDDLE  ALT=\"%284x-7%29=0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=4x-7=0 ALIGN=MIDDLE  ALT=\"4x-7=0\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=7%2F4 ALIGN=MIDDLE  ALT=\"x=7%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "There are 20 roots at x=7/4.<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+graph%28+300%2C+300%2C+-2%2C+3%2C+-10%2C+10%2C+%284x-7%29%5E20%29+ ALIGN=MIDDLE  ALT=\"+graph%28+300%2C+300%2C+-2%2C+3%2C+-10%2C+10%2C+%284x-7%29%5E20%29+\"   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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