Has that familiar curve to it

To Form

The: he harmonic mean (HM)

 of 

two numbers

As

 one Idea

with three aspects

Begin with

Idea as

 a and add b

Names

one and two

Altitude and Base

numerals

2  and 3 

N and N+M

is found using the formula 

HyMn = 2  a b 

         /// 

       a + b

Double the form created by forming

AB into rectangular area AB

also called Surface AB

Divide the Double surface 

by

The sum of the length of the line 

generated by Adding

A and B

  derived from taking the reciprocal of the average of their reciprocals: 

HM = 2 

         /

                    1/a + 1/b