document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=197935>Question 197935</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hi all, I have a bit of a problem with a Matrices question I'm trying to answer.<BR>\n" );
document.write( "I need to find the product of the following matrices:<BR>\n" );
document.write( "A=<BR>\n" );
document.write( "2 -1  2 <BR>\n" );
document.write( "  -1  2  0<BR>\n" );
document.write( "   0  0  2<BR>\n" );
document.write( "   2  0  -3<BR>\n" );
document.write( "    <BR>\n" );
document.write( "B=<BR>\n" );
document.write( "2 -1  2 <BR>\n" );
document.write( "  1  2  0<BR>\n" );
document.write( "  0  0  2<BR>\n" );
document.write( "     \r<BR>\n" );
document.write( "\n" );
document.write( "I also need to state which of the two products should be taken -A . B or B . A.<BR>\n" );
document.write( "Can we sum up and A and B?\r<BR>\n" );
document.write( "\n" );
document.write( "Any help would be great.<BR>\n" );
document.write( "-Nick </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #148424 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=148424\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> find the product of the following matrices:<BR>\n" );
document.write( "A=<BR>\n" );
document.write( "2 -1 2 <BR>\n" );
document.write( "-1 2 0<BR>\n" );
document.write( "0 0 2<BR>\n" );
document.write( "2 0 -3<BR>\n" );
document.write( "---<BR>\n" );
document.write( "A is a 4 by 3 matrix.<BR>\n" );
document.write( "--------------------------\r<BR>\n" );
document.write( "\n" );
document.write( "B=<BR>\n" );
document.write( "2 -1 2 <BR>\n" );
document.write( "1 2 0<BR>\n" );
document.write( "0 0 2<BR>\n" );
document.write( "---<BR>\n" );
document.write( "B is a 3 by 3 matrix<BR>\n" );
document.write( "--------------------------\r<BR>\n" );
document.write( "\n" );
document.write( "I also need to state which of the two products should be taken -A . B or B . A.<BR>\n" );
document.write( "A*B works because the column count on A equals the row count on B.<BR>\n" );
document.write( "------------------------<BR>\n" );
document.write( "Can we sum up and A and B? <BR>\n" );
document.write( "No, because the dimensions are not the same.<BR>\n" );
document.write( "-------------------------------------------------------<BR>\n" );
document.write( "A=<BR>\n" );
document.write( "   2 -1  2 <BR>\n" );
document.write( "  -1  2  0<BR>\n" );
document.write( "   0  0  2<BR>\n" );
document.write( "   2  0  -3<BR>\n" );
document.write( "    <BR>\n" );
document.write( "B=<BR>\n" );
document.write( "  2 -1  2 <BR>\n" );
document.write( "  1  2  0<BR>\n" );
document.write( "  0  0  2<BR>\n" );
document.write( "     <BR>\n" );
document.write( "AB = <BR>\n" );
document.write( "3  -4  4<BR>\n" );
document.write( "0   5 -2<BR>\n" );
document.write( "0   0  4<BR>\n" );
document.write( "4  -2 -2<BR>\n" );
document.write( "====================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );