Question

Which of the following is not a geometric sequence?

• A. $2,4,8,16,\dots$.
• B. $\frac{1}{9},\frac{-1}{27},\frac{1}{81},\frac{-1}{243},\dots \dots$
• C. $0.01,0001,000001\dots \dots$
• D. None of these

Answer 1

Answer: (D)

$2,4,8,16,\dots$ is a geometric sequence with common ratio 2 .
$\frac{1}{9},\frac{-1}{27},\frac{1}{81},\frac{-1}{243},\dots$ is a geometric sequence with common ratio $\frac{-1}{3}$
$.01,.0001,.000001$, common ratio 01 .
is a geometric sequence with
Hence, (a), (b) and (c) are the examples of geometric sequence.