Question

Write the nth rule for the following geometric sequence. Then find the fifth term. ( you are given the first term and the common ratio)

Answer 1

The geometric sequence is given by:

`a_n=ar^(n-1)`

Where:

a = first term of the sequence

r = common ratio

therefore:

`\begin{gathered} a_n=-2\cdot4^(n-1)^{} \\ n=5 \\ a_5=-2\cdot4^(5-1) \\ a_5=-2\cdot4^4 \\ a_5=-2\cdot256 \\ a_5=-512 \end{gathered}`