document.write( "Question 1105522: x+2y+3z+4w=0
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document.write( "8x+5y+z+4w=0
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document.write( "5x+6y+8z+w=0
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document.write( "8x+3y+7z+2w=0
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document.write( "solve using determinant \n" );
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Algebra.Com's Answer #720365 by ikleyn(52908) You can put this solution on YOUR website! . \n" ); document.write( " \r\n" ); document.write( "Your matrix\r\n" ); document.write( "\r\n" ); document.write( " X1 X2 X3 X4 b\r\n" ); document.write( "1 1 2 3 4 0\r\n" ); document.write( "2 8 5 1 4 0\r\n" ); document.write( "3 5 6 8 1 0\r\n" ); document.write( "4 8 3 7 2 0\r\n" ); document.write( "\r\n" ); document.write( "Write down the main matrix and find its determinant\r\n" ); document.write( "\r\n" ); document.write( " X1 X2 X3 X4\r\n" ); document.write( "1 1 2 3 4\r\n" ); document.write( "2 8 5 1 4\r\n" ); document.write( "3 5 6 8 1\r\n" ); document.write( "4 8 3 7 2\r\n" ); document.write( "\r\n" ); document.write( "Δ = -1034 <<<---=== Since the determinant is not zero, the solution to the system is the zero vector.\r\n" ); document.write( " Explicit calculations below confirm this fact.\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "Replace the 1st column of the main matrix with the solution vector and find its determinant\r\n" ); document.write( "\r\n" ); document.write( " X1 X2 X3 X4\r\n" ); document.write( "1 0 2 3 4\r\n" ); document.write( "2 0 5 1 4\r\n" ); document.write( "3 0 6 8 1\r\n" ); document.write( "4 0 3 7 2\r\n" ); document.write( "\r\n" ); document.write( "Δ1 = 0\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "Replace the 2nd column of the main matrix with the solution vector and find its determinant\r\n" ); document.write( "\r\n" ); document.write( " X1 X2 X3 X4\r\n" ); document.write( "1 1 0 3 4\r\n" ); document.write( "2 8 0 1 4\r\n" ); document.write( "3 5 0 8 1\r\n" ); document.write( "4 8 0 7 2\r\n" ); document.write( "\r\n" ); document.write( "Δ2 = 0\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "Replace the 3rd column of the main matrix with the solution vector and find its determinant\r\n" ); document.write( "\r\n" ); document.write( " X1 X2 X3 X4\r\n" ); document.write( "1 1 2 0 4\r\n" ); document.write( "2 8 5 0 4\r\n" ); document.write( "3 5 6 0 1\r\n" ); document.write( "4 8 3 0 2\r\n" ); document.write( "\r\n" ); document.write( "Δ3 = 0\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "Replace the 4th column of the main matrix with the solution vector and find its determinant\r\n" ); document.write( "\r\n" ); document.write( " X1 X2 X3 X4\r\n" ); document.write( "1 1 2 3 0\r\n" ); document.write( "2 8 5 1 0\r\n" ); document.write( "3 5 6 8 0\r\n" ); document.write( "4 8 3 7 0\r\n" ); document.write( "\r\n" ); document.write( "Δ4 = 0\r\n" ); document.write( "\r\n" ); document.write( "\r\n" ); document.write( "x1 = Δ1 / Δ = 0 / (-1034) = 0\r\n" ); document.write( "x2 = Δ2 / Δ = 0 / (-1034) = 0\r\n" ); document.write( "x3 = Δ3 / Δ = 0 / (-1034) = 0\r\n" ); document.write( "x4 = Δ4 / Δ = 0 / (-1034) = 0\r\n" ); document.write( "\r\n" ); document.write( "Solution set:\r\n" ); document.write( "\r\n" ); document.write( "x1 = 0\r\n" ); document.write( "x2 = 0\r\n" ); document.write( "x3 = 0\r\n" ); document.write( "x4 = 0\r\n" ); document.write( "\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |