This symbol, pronounced Sima, in the formula means adding all the items that are gradually accumulated, that is, the sum of all the items. Every item here refers to
Where I is marked by its range of values above and below the letter Sigma, here from 1 to n,
So the symbol of this formula represents the cumulative calculation of n terms Ji from 1 to n.
Now I understand.
The meaning of this formula, the meaning of the formula in the denominator is immediately understood:
The meaning of this formula is: accumulate from 1 to n to calculate n hi.
(3) understand the meaning of the above two formulas, and then whether the formula you want works.
According to the meaning of the specific item given in the above formula, the value of b can be calculated, and it is more convenient to write a program to calculate it. Manual calculation is still very troublesome.