SOLUTION: a) The first four terms of a sequence are given as 2/3 ,-2/9 , 2/27 ,-2/81 (i) Determine U_n, the general form for the n^th term of the sequence [2] (ii) Calculate

Algebra ->  Sequences-and-series -> SOLUTION: a) The first four terms of a sequence are given as 2/3 ,-2/9 , 2/27 ,-2/81 (i) Determine U_n, the general form for the n^th term of the sequence [2] (ii) Calculate       Log On


   



Question 866098: a) The first four terms of a sequence are given as
2/3 ,-2/9 , 2/27 ,-2/81
(i) Determine U_n, the general form for the n^th term of the sequence [2]
(ii) Calculate the difference between the 10th and 8th term of the sequence. [3]

Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
r=-1/3
i) Tn = 2/3 *(-1/3)^(n - 1)
Tn = 2/3 *(-1/3)^(9)=-2/59049
Tn = 2/3 *(-1/3)^(7)=-2/6561
ii) D=2/3 *(-1/3)^(9)-2/3*(-1/3)^(7)=16/59049