# Calculate the geometric series? Please

##### 1 Answer

This is not geometric, but using the Maclaurin series expansion for arctangent, we see its value is

#### Explanation:

A geometric series is generally in the form

We have the series

As a result of the **not** geometric.

Geometric series do not have the index

However, we can still find the exact value of this series.

Recall the following Maclaurin series expansion for the arctangent:

For our series, we can see that

Well,

So, that's why in the given summation,

Then, since our series is equal to