document.write( "Question 1060844: I would like to know what formula can I use to solve the nth term of this particular sequence. 5, 12, 25, 50, 93 \n" ); document.write( "
Algebra.Com's Answer #675707 by rothauserc(4718)\"\" \"About 
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This is a cubic sequence, the general form is
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\n" ); document.write( "an^3 +bn^2 +cn +d = 0
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\n" ); document.write( "the method of differences confirms a common difference of 6 at the 3rd level
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\n" ); document.write( "using the first four terms, we get the following points
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\n" ); document.write( "(1,5), (2,12), (3,25), (4,50)
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\n" ); document.write( "We have four equations in 4 unknowns
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\n" ); document.write( "a +b +c +d = 5
\n" ); document.write( "8a +4b +2c +d = 12
\n" ); document.write( "27a +9b +3c +d = 25
\n" ); document.write( "64a +16b +4c +d = 50
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\n" ); document.write( "use Cramer's rule calculator
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\n" ); document.write( "a = 1, b = -3, c = 9, d = -2
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\n" ); document.write( "x(n) = n^3 -3n^2 +9n -2
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