document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1201081>Question 1201081</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Consider the function f(x) = (x^(4/5))(x-10). Find the the two numbers where f\"(x) = 0 or f\"(x) is undefined. Also, find the intervals where f(x) is concave up or down.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #837817 by </B><A HREF=/tutors/aboutme.mpl?userid=amarjeeth123><B>amarjeeth123(569)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=amarjeeth123><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=837817\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The given function is f(x)=(x^(4/5))(x-10).<BR>\n" );
document.write( "f'(x)=(9x-40)/(5*(x^(1/5)))<BR>\n" );
document.write( "f''(x)=(36x+40)/(25*(x^(6/5)))<BR>\n" );
document.write( "The points where f\"(x)=0 are given by 36x+40=0 or 36x=-40 or x=-(10/9) and x=0.<BR>\n" );
document.write( "The points where f\"(x)=0 or undefined are x=-(10/9) and x=0.\r<BR>\n" );
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document.write( "Concave Downward:(-inf,-10/9)<BR>\n" );
document.write( "Concave Upward:(-10/9,0)U(0,inf)<BR>\n" );
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