document.write( "Question 519652: What is the inverse of this matrix? [6 2]
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Algebra.Com's Answer #345724 by Edwin McCravy(20081) $\"\"$ $\"About$

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document.write( "The rule for finding the inverse of a 2x2 matrix:\r\n" );
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document.write( "1. Swap the upper left and lower right elements.\r\n" );
document.write( "2. Change the signs of the upper right and lower left elements.\r\n" );
document.write( "3. Divide each element by the determinate of the matrix.  \r\n" );
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document.write( "[Note: It doesn't matter whether you use the determinant of the original\r\n" );
document.write( " matrix or the altered one after step 2, since they have the same determinant]\r\n" );
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document.write( "1. Swap the upper left and lower right elements.\r\n" );
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document.write( "2. Change the signs of the upper right and lower left elements.\r\n" );
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document.write( "3. Divide each element by the determinate of the matrix.\r\n" );
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document.write( "The determinant of the original matrix is 6×3-2×8 = 18-16 = 2\r\n" );
document.write( "[Note: that's the same as 3×6-(-2)(-8)=18-16 = 2]\r\n" );
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document.write( "You get\r\n" );
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document.write( "which simplifies to:\r\n" );
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document.write( "Edwin

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