document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=60607>Question 60607</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0023557222/algebrahomeworkh>introduction to mathmatical statistics</A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> please help me in this  <BR>\n" );
document.write( "  let x have the p.d.f   f(x)= (x+2)/18 , -2<x<4 , zero elsewhere <BR>\n" );
document.write( "find E[(x+2)^3], and E[6x-2(x+2)^3] </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #409852 by </B><A HREF=/tutors/aboutme.mpl?userid=NM653264><B>NM653264(1)</B></A><img src=\"/images/stars/iconNewId_16x16.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=NM653264><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=409852\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> E(X) = the integral from 4 to -2 of xf(x)dx<BR>\n" );
document.write( "=Integral of x(x+2/18) = (x^2+2x)/18 <BR>\n" );
document.write( "now integrate from -2 to 4 so you get E(X)=2\r<BR>\n" );
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document.write( "E((x+2)^3) = E(2+2)^3 =64\r<BR>\n" );
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document.write( "E[6x-2(x+2)^3]=6(2)-2(64) = -116 </SPAN>\n" );
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