Geometric Series - Problem 14

A geometric sequence is a number pattern where you multiply a term by some fixed ratio, r, in order to get the next term. We can find any term in the list using a shortcut formula called the explicit formula. We could also describe the pattern using a recursive formula, but it's less useful because we'd need to know the term before in order to find a new term. If you want to add these terms in your pattern, then you have what is called a geometric series. It is often represented using capital Greek letter Sigma. To find a sum, you'll need to know how many terms you're adding, the first term, and the ratio, r, for the pattern.