Answer:
In geometric sequence you divide the terms. As I will show you the calculations step by step. Hopefully this becomes clear and helpful to you
Explanation:
-2187÷6561
= -0.3333...
a8=a1 r^8-1
=(4374)(-0.3)^8-1
=(4374)(-0.3)^7
=(4374)(-4.572473708×10^-4)
=-2
Therefore a8= -2