Question

For the following geometric sequence find the recursive formula and the 5th term in the sequence. In your final answer, include all of your work. {-4, 12, -36, ...}

Answer 1

The common ration is 12/ -4 = -3

the explicit term is (-4)* -3^(n-1)
so the 5th term is -4*-3^4 =  -324

Im a bit hazy about the recursive formula 

i think its  a(n+1) =  an * -3