9514 1404 393
Answer:
an = 2(-4)^(n-1)
Explanation:
The general form of the explicit formula for a geometric series with first term a1 and common ratio r is ...
an = a1·r^(n-1)
Your sequence has a1=2 and r=-8/2 = -4. So, the explicit formula is ...
an = 2(-4)^(n-1)