document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=166576>Question 166576</A>: <I><SPAN STYLE=\"word-break: break-all;\"> can someone please help me with this problem:\r<BR>\n" );
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document.write( "Find the order of the matrix product AB and the product BA, whenever the products exist.\r<BR>\n" );
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document.write( "A is 2 x 1, B is 1 x 1\r<BR>\n" );
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document.write( "a. AB is 2 x 1, BA is nonexistent.<BR>\n" );
document.write( "b. AB is nonexistent, BA is 1 x 2<BR>\n" );
document.write( "c. AB is 1 x 2, BA is 1 x 1<BR>\n" );
document.write( "d. AB is 2 x 2, BA is 1 x 1 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #122785 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=122785\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Find the order of the matrix product AB and the product BA, whenever the products exist.<BR>\n" );
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document.write( "Rule: The number of columns on the left must be the same as the number<BR>\n" );
document.write( "of rows on the right. <BR>\n" );
document.write( "The product of an [x by y matrix] and a [w by z matrix] will be  x by z]<BR>\n" );
document.write( "To have a product, y must bethe same as w.<BR>\n" );
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document.write( "A is 2 x 1, B is 1 x 1 <BR>\n" );
document.write( "AB ?<BR>\n" );
document.write( "Can be multiplied because 1=1<BR>\n" );
document.write( "Product will be 2 x 1<BR>\n" );
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document.write( "BA ?<BR>\n" );
document.write( "Cannot be multiplied because 1 is not equal to 2<BR>\n" );
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document.write( "Answer: a<BR>\n" );
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document.write( "Cheers,<BR>\n" );
document.write( "Stan H.<BR>\n" );
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document.write( "a. AB is 2 x 1, BA is nonexistent.<BR>\n" );
document.write( "b. AB is nonexistent, BA is 1 x 2<BR>\n" );
document.write( "c. AB is 1 x 2, BA is 1 x 1<BR>\n" );
document.write( "d. AB is 2 x 2, BA is 1 x 1<BR>\n" );
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