A park has the shape of a regular hexagon
of sides 2km each. A boy walks a distance
of 5km along the sides of the park.
What is the direct distance between
the start point and the end point?
I heard this sum can be close using the Digamma function.
Please help me use it. i don′t know it.
sum of nth term: (1/(1.2.3)) + (1/(4.5.6)) + (1/(7.8.9)) + ...