Question

I need help with this Algebra page, I only need to do two of the problems

Answer 1

12)

Given data:

The given series is 5, 15, 45, 135, 405...

The geometric ratio is,

`\begin{gathered} r=(15)/(5) \\ =3 \end{gathered}`

The expression for recursive rule is,

`\begin{gathered} a_n=a_(n-1)(r)^{} \\ =a_(n-1)(3) \end{gathered}`

The expression for the explicit formula is,

`\begin{gathered} a_n=ar^(n-1) \\ =5(3)^(n-1) \end{gathered}`

Thus, the recursive rule is an-1(3), and explicit rule is 5(3)^(n-1).