Answer:
This is a geometric sequence with first term -2 and common ratio -2.
Explicit formula: a_n = (-2)^n
Step-by-step explanation:
4/-2 = -2
-8/4 = -2
This is a geometric sequence with first term -2 and common ratio -2.
a_1 = -2
a_n = -2 × a_n-1
a_1 = -2 = (-2)^1
a_2 = -2 × (-2) = (-2)^2
a_3 = -2 × (-2) × (-2) = (-2)^3
a_n = (-2)^n