document.write( "Question 1082118: Use differences to find a pattern in the sequence. -1,-4,-10,-11,-1, 26,76. Assuming that the pattern​ continues, the eighth term should be
\n" ); document.write( "I cannot figure out how to work this problem. Please help. \n" ); document.write( "
Algebra.Com's Answer #696208 by solver91311(24713)\"\" \"About 
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document.write( "-1      -4     -10      -11      -1      26      76      \r\n" );
document.write( "    -3      -6      -1       10      27      50      \r\n" );
document.write( "        -3       5       11      17      23      \r\n" );
document.write( "             8       6        6       6       \r\n" );
document.write( "                -2        0       0      \r\n" );
document.write( "                     2        0      \r\n" );
document.write( "                         -2     \r\n" );
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\n" ); document.write( "\n" ); document.write( "Calculate the differences between each pair of elements in the sequence. Then calculate the differences between each pair of differences, and so on until you get a row with more than one element where all of the elements are the same. This only works when you have a convergent sequence. Unfortunately, your given sequence does not converge, hence the differences method is inconclusive.\r
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\n" ); document.write( "\n" ); document.write( "The only way I know to get the next element in the sequence is to assign a sequential x value to each of the sequence elements forming a set of ordered pairs of the form and then find a polynomial of degree that fits the data. Your next element will be where is the derived polynomial. To do this you either use a graphing app that has a curve fitting utility, or you grind a 7X7 system of linear equations.\r
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\n" ); document.write( "\n" ); document.write( "My graph program gave me and then calculated \r
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\n" ); document.write( "\n" ); document.write( "John
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\n" ); document.write( "My calculator said it, I believe it, that settles it
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