document.write( "Question 274093: Use the fact that if $\"A=%28matrix%282%2C2%2Ca%2Cb%2Cc%2Cd%29%29\"$ \r
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Algebra.Com's Answer #200081 by Edwin McCravy(20065) $\"\"$ $\"About$

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Use the fact that if $\"A=%28matrix%282%2C2%2Ca%2Cb%2Cc%2Cd%29%29\"$ \r
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document.write( "You just need to learn how to substitute numbers for letters,\r\n" );
document.write( "which is very easy to do.  All you do is:\r\n" );
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document.write( "1. Put 0 or (0) everywhere there is an \"a\",\r\n" );
document.write( "2. Put 3 or (3) everywhere there is a \"b\".\r\n" );
document.write( "3. Put 4 or (4) everywhere there is a \"c\".\r\n" );
document.write( "4. Put -2 or (-2) everywhere there is a \"d\".\r\n" );
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document.write( "So comparing the matrix\r\n" );
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document.write( "to your matrix,\r\n" );
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document.write( "then do the substituting in\r\n" );
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document.write( "and you will have:\r\n" );
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document.write( "  \r\n" );
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document.write( "which is the inverse of that matrix, unsimplified.\r\n" );
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document.write( "Now you only have to simplify everything:\r\n" );
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document.write( "Now distribute by multiplying the  by every \r\n" );
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document.write( "Then simplify\r\n" );
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document.write( "Edwin

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