Question

Tell whether each sequence is arithmetic. Justify your answer. If the sequence is arithmetic, write a function rule to represent it. A. 128, 64, 32, 16, ... B. 3, 3.25, 3.5, 3.75, ...

Answer 1

A) geometric:
.. a[n] = 128*(1/2)^(n -1)

B) arithmetic:
.. a[n] = 3 +0.25*(n -1)

_____
As you know, the general term of an aritnmetic sequence is
.. a[n] = a[1] +d*(n -1)
.. ... where a[1] is the first term (n=1) and d is the common difference. n is the term number.