The geometric mean is defined as the nth root of the product of n numbers.
This means, you multiply all the numbers together
5×8=40
And then you take the nth root of that number. In this case, it's the square root, but if there were more numbers, like three or four, it would be the cube and fourth root, respectively.
√40 = 6.32455532
So, the geometric mean of 5 and 8 is 6.32455532
