document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=673581>Question 673581</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Evaluate the expression\r<BR>\n" );
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document.write( "  a) 8C2<BR>\n" );
document.write( "  b) 8P2\r<BR>\n" );
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document.write( "Please help me on this. I need to understand , I have a final coming up. <BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #418735 by </B><A HREF=/tutors/aboutme.mpl?userid=sachi><B>sachi(548)</B></A><img src=\"/images/stars/stars-10.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=sachi><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=sachi><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=418735\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In general <BR>\n" );
document.write( "nCr=n!/r!(n-r)!=n(n-1)(n-2)......3 2 1/r(r-1)!....2 1*(n-r)(n-r-1)...21<BR>\n" );
document.write( "so 8C2=8!/2!6!=8*7*6*5*4*3*2*1/2*1*6*5*4*3*2*1=28<BR>\n" );
document.write( "nPr=n!/(n-r)!=n(n-1)(n-2)......3 2 1/(n-r)(n-r-1)...21<BR>\n" );
document.write( "so 8P2=8!/6!=8*7*6*5*4*3*2*1/6*5*4*3*2*1=56<BR>\n" );
document.write( "ans </SPAN>\n" );
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