This document discusses geometric sequences and series. It defines a geometric sequence as a sequence where each term after the first is found by multiplying the preceding term by a common ratio. It provides formulas for finding the nth term of a geometric sequence and the nth partial sum, where the nth term is the first term multiplied by the common ratio to the power of n-1, and the nth partial sum is the first term multiplied by 1 minus the common ratio to the nth power, divided by 1 minus the common ratio.