document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=176155>Question 176155</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Are these matrices inverses of each other? Show why or why not.\r<BR>\n" );
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document.write( "[2 -1]<BR>\n" );
document.write( "[-3 1]\r<BR>\n" );
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document.write( "[-1 -1]<BR>\n" );
document.write( "[-3 -2] </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #131238 by </B><A HREF=/tutors/aboutme.mpl?userid=Fombitz><B>Fombitz(32388)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Fombitz><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=Fombitz><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=131238\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The inverse of a 2x2 matrix [A], where<BR>\n" );
document.write( "[A]=<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28matrix%282%2C2%2Ca%2Cb%2Cc%2Cd%29%29 ALIGN=MIDDLE  ALT=\"%28matrix%282%2C2%2Ca%2Cb%2Cc%2Cd%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "is given by <BR>\n" );
document.write( "[A]inv=<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=DELTA%2A%28matrix%282%2C2%2Cd%2C-b%2C-c%2Ca%29%29 ALIGN=MIDDLE  ALT=\"DELTA%2A%28matrix%282%2C2%2Cd%2C-b%2C-c%2Ca%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "where <BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=DELTA=1%2F%28ad-bc%29 ALIGN=MIDDLE  ALT=\"DELTA=1%2F%28ad-bc%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "In your case,<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=a=2 ALIGN=MIDDLE  ALT=\"a=2\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=b=-1 ALIGN=MIDDLE  ALT=\"b=-1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=c=-3 ALIGN=MIDDLE  ALT=\"c=-3\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=d=1 ALIGN=MIDDLE  ALT=\"d=1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=DELTA=1%2F%282%281%29-%28-1%29%28-3%29%29 ALIGN=MIDDLE  ALT=\"DELTA=1%2F%282%281%29-%28-1%29%28-3%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=DELTA=1%2F%282-3%29 ALIGN=MIDDLE  ALT=\"DELTA=1%2F%282-3%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=DELTA=-1 ALIGN=MIDDLE  ALT=\"DELTA=-1\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "[A]inv=<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28-1%29%2A%28matrix%282%2C2%2C1%2C1%2C3%2C2%29%29 ALIGN=MIDDLE  ALT=\"%28-1%29%2A%28matrix%282%2C2%2C1%2C1%2C3%2C2%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "[A]inv=<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28matrix%282%2C2%2C-1%2C-1%2C-3%2C-2%29%29 ALIGN=MIDDLE  ALT=\"%28matrix%282%2C2%2C-1%2C-1%2C-3%2C-2%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "This matrix matches the inverse given.<BR>\n" );
document.write( "Yes, they are inverses. </SPAN>\n" );
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