document.write( "Question 557397: rank of the matrix ⎡
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Algebra.Com's Answer #362593 by Edwin McCravy(20060)\"\" \"About 
You can put this solution on YOUR website!
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document.write( "4 5 6 7\r\n" );
document.write( "3 4 5 6\r\n" );
document.write( "2 3 4 5\r\n" );
document.write( "1 2 3 4\r\n" );
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document.write( "Multiply row 2 by -1 and add it to row 1\r\n" );
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document.write( "1 1 1 1\r\n" );
document.write( "3 4 5 6\r\n" );
document.write( "2 3 4 5\r\n" );
document.write( "1 2 3 4\r\n" );
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document.write( "Multiply row 3 by -1 and add it to row 2\r\n" );
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document.write( "1 1 1 1\r\n" );
document.write( "1 1 1 1\r\n" );
document.write( "2 3 4 5\r\n" );
document.write( "1 2 3 4\r\n" );
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document.write( "Multiply row 4 by -1 and add it to row 3\r\n" );
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document.write( "1 1 1 1\r\n" );
document.write( "1 1 1 1\r\n" );
document.write( "1 1 1 1\r\n" );
document.write( "1 2 3 4\r\n" );
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document.write( "Multiply row 1 by -1 and add it to row 2\r\n" );
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document.write( "1 1 1 1\r\n" );
document.write( "0 0 0 0\r\n" );
document.write( "1 1 1 1\r\n" );
document.write( "1 2 3 4\r\n" );
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document.write( "Multiply row 1 by -1 and add it to row 3\r\n" );
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document.write( "1 1 1 1\r\n" );
document.write( "0 0 0 0\r\n" );
document.write( "0 0 0 0\r\n" );
document.write( "1 2 3 4\r\n" );
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document.write( "Swap rows 2 and 4\r\n" );
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document.write( "1 1 1 1\r\n" );
document.write( "1 2 3 4\r\n" );
document.write( "0 0 0 0\r\n" );
document.write( "0 0 0 0\r\n" );
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document.write( "Multiply row 1 by -1 and add it to row 2\r\n" );
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document.write( "1 1 1 1\r\n" );
document.write( "0 1 2 3\r\n" );
document.write( "0 0 0 0\r\n" );
document.write( "0 0 0 0\r\n" );
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document.write( "Multiply row 2 by -1 and add it to row 1\r\n" );
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document.write( "1 0 -1 -2\r\n" );
document.write( "0 1  2  3\r\n" );
document.write( "0 0  0  0\r\n" );
document.write( "0 0  0  0\r\n" );
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document.write( "That's in row reduced echelon form.  The number of\r\n" );
document.write( "not-all-zero rows is 2, so its rank is 2.\r\n" );
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document.write( "Edwin
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