document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=117507>Question 117507</A>: <I><SPAN STYLE=\"word-break: break-all;\"> what are the steps when using a graphing calculator to solve systems using inverse matrices  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #85611 by </B><A HREF=/tutors/aboutme.mpl?userid=bucky><B>bucky(2189)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=bucky><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=85611\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Probably varies depending on the model of the calculator. On the TI-89 it goes this way:<BR>\n" );
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document.write( "Suppose you are given a 3 by 3 matrix to inverse. And suppose that matrix is:<BR>\n" );
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document.write( "+1 0 0<BR>\n" );
document.write( "-1 1 0<BR>\n" );
document.write( "+1 1 1<BR>\n" );
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document.write( "The plus signs are just added for typing purposes in this answer. The minus sign is needed,<BR>\n" );
document.write( "but the plus signs are just inserted to keep the columns of numbers aligned in the typed<BR>\n" );
document.write( "version.<BR>\n" );
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document.write( "On the entry line ... enter exactly as below:<BR>\n" );
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document.write( "([1,0,0;-1,1,0;1,1,1])^-1<BR>\n" );
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document.write( "A couple of notes about this entry:<BR>\n" );
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document.write( "Note that there is a difference between the symbols \"(\" and \"[\" and their counterparts in <BR>\n" );
document.write( "the reverse direction. Do not interchange them or use a parenthesis in place of a bracket.<BR>\n" );
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document.write( "Note that the symbol representing the end of a line in the matrix is a semicolon, not <BR>\n" );
document.write( "a colon.<BR>\n" );
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document.write( "Note that the minus sign at the beginning of the second line is from the key that looks<BR>\n" );
document.write( "like (-). It is not the subtraction function key that has just a minus sign on it. The same<BR>\n" );
document.write( "thing applies for the minus sign in the exponent ... use the (-) key not the - key to <BR>\n" );
document.write( "enter the exponent -1.<BR>\n" );
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document.write( "When you type the line exactly as shown above, you are raising the matrix to the minus 1 power.<BR>\n" );
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document.write( "You will get an answer that shows the inversed matrix is:<BR>\n" );
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document.write( "+1 +0 0<BR>\n" );
document.write( "+1 +1 0<BR>\n" );
document.write( "-2 -1 1<BR>\n" );
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document.write( "As before, the plus signs are added here just to keep the number columns aligned. They<BR>\n" );
document.write( "do not show in the calculator's answer but the columns are aligned.<BR>\n" );
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document.write( "Hope this helps you with your calculator. If it does not, read your instruction book on how<BR>\n" );
document.write( "to enter a matrix. Then try raising it to the -1 power to see if that procedure works.<BR>\n" );
document.write( "Use the problem and the answer above as a check to see if the calculator gives the answer<BR>\n" );
document.write( "above.<BR>\n" );
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document.write( "Hope this helps you out ...\r<BR>\n" );
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