Answer:
D.) a(n) = 4 * (1/3)^(n-1)
Step-by-step explanation:
a(1) = 1/3 * a(1-1) = 1/3 * a(0) = 4, so that
1/3 * a(0) = 4
a(0) = 12.
Answer choice D.) is such that a(0) = 4 (1/3)^(0-1) = 4*(1/3)^(-1) = 4 * 3 = 12, and assuming that the problem is well posed (i.e., exactly one of the answer choices is correct), we deduce that D.) is the correct answer choice.
