Question

Use the following recursive formula to answer the question.

A1=-3/2
an=an-1+1/2
what’s is a9?

Answer 1

Explanation:

a2=a1+1/2=-1

a3=a2+1/2=-1/2, then we have common difference 0.5

a9=a1+(n-1)d

a9=-3/2+(8)0.5=5/2