document.write( "Question 210252: make a conjecture in terms of Q(n)(find the nth term) for the following sequence & then find the 100th term:n= 1 2 3 4 5 6
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document.write( " Q= 3 12 25 42 63 88\r
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document.write( "Cannot figure out any part of this...I would really appreciate any help at this point!
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document.write( "Thanks! \n" );
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Algebra.Com's Answer #158884 by scott8148(6628)![]() ![]() You can put this solution on YOUR website! the differences between consecutive Q terms are ___ 9, 13, 17, 21, 25\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "the difference between consecutive terms of the 1st set of differences is equal to 4 and is constant \n" ); document.write( "___ this means that the conjecture is a second order expression (2nd differences constant)\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Q(n) = an^2 + bn + c\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Q(1) = a(1^2) + b(1) + c ___ 3 = a + b + c ___ 3 - a - b = c\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Q(2) = a(2^2) + b(2) + c ___ 12 = 4a + 2b + c \n" ); document.write( "substituting ___ 12 = 4a + 2b + 3 - a - b ___ 9 = 3a + b\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Q(3) = a(3^2) + b(3) + c ___ 25 = 9a + 3b + c \n" ); document.write( "substituting ___ 25 = 9a + 3b + 3 - a - b ___ 22 = 8a + 2b ___ 11 = 4a + b\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "subtracting equations ___ 2 = a\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "substituting ___ 11 = 4(2) + b ___ 3 = b\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "substituting ___ 3 - 2 - 3 = c ___ -2 = c\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Q(n) = 2n^2 + 3n - 2\r \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Q(100) = 2(100^2) + 3(100) - 2 = 20298 \n" ); document.write( " |