Definition:Geometric Mean

Let $$x_1, x_2, \ldots, x_n \in \mathbb{R}$$ be real numbers which are all positive.

The geometric mean of $$x_1, x_2, \ldots, x_n$$ is defined as:

$$G_n = \left({\prod_{k=1}^n x_k}\right)^{1/n}$$

That is, to find out the geometric mean of a set of $$n$$ numbers, multiply them together and take the $n$th root.