document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=910808>Question 910808</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Evaluate the following expression:\r<BR>\n" );
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document.write( "C(n,2)\r<BR>\n" );
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document.write( "I understand that it would be:\r<BR>\n" );
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document.write( "= n! / r!(n-r)!<BR>\n" );
document.write( "= n! / 2!(n-2)!\r<BR>\n" );
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document.write( "I'm just not sure how to simplify this? \r<BR>\n" );
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document.write( "An explanation and answer would be really appreciated :) </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #552683 by </B><A HREF=/tutors/aboutme.mpl?userid=ewatrrr><B>ewatrrr(24785)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ewatrrr><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=ewatrrr><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=552683\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> = n! / 2!(n-2)!  = (n(n-1)(n-2)(n-3)...)/(2!(n-2)(n-3)...) = n(n-1)/2<BR>\n" );
document.write( "Ex:<BR>\n" );
document.write( "5C2 = 5*4/2 = 10 </SPAN>\n" );
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