What is the 6th term of the geometric sequence where a1 = 128 and a3 = 8?
Solution:
The nth term of a geometric sequence is given by
an = a1 × rn - 1 --- (1)
Given, a1 = 128, a3 = 8
To find r put the value of a1 and a3 in (1)
⇒ 8 = 128 × r2
⇒ r2 = 8/128
⇒ r2 = 0.0625
⇒ r = 0.25
Now, find a6
a6 = a1 × r5
a6 = 128 × (0.25)5
= 128 × 0.000976
a6 = 0.125
Therefore, the 6th term of the geometric sequence is 0.125
What is the 6th term of the geometric sequence where a1 = 128 and a3 = 8?
Summary:
The 6th term of the geometric sequence where a1 = 128 and a3 = 8 is 0.125
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