Question

I’m confused what this is. HELP! Only do 4.

Answer 1

4. 54, -18, 6, -2

First term a₁=54

common ratio  r=-18/54 = 6/-18 = -2/6 = -1/3

Recursive form:

a[1]=54

a[n] = (-1/3) a[n-1]   for n>1

Explicit formula:

$a_n = 54 (-\frac 1 3)^{n - 1}$