Find the sixth term of a geometric sequence with t5 = 24 and t8 = 3.
Solution:
Given, t5 = 24 and t8 = 3
The n-th term of the geometric sequence is given by
\(t_{n}=t(r)^{(n-1)}\)
\(\\t_{5}=t(r)^{(5-1)}\\24=tr^{4}\)
t = 24/r4
\(\\t_{8}=t(r)^{(8-1)}\\3=tr^{7}\)
Now, 3 = (24/r4)(r7)
3 = 24r3
r3 = 3/24
r3 = 1/8
Taking cube root,
r = 1/2
Now, 24 = a(1/2)4
24 = a(1/16)
a = 384
The sixth term of the sequence, \(\\t_{6}=tr^{(6-1)}\\t_{6}=384(1/2)^{5})\\t_{6}=384(1/32)\)
\(t_{6}=12\)
Therefore, the sixth term is 12.
Find the sixth term of a geometric sequence with t5 = 24 and t8 = 3.
Summary:
The sixth term of a geometric sequence with t5 = 24 and t8 = 3 is 12.
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