Question

What is 2 in summation notation

Answer 1

Answer: Double sum is nothing more than sum of a sum. If the elements of the sum have two indices and you want to add the index one by one, then you use double sums. In calculating double summations, here are the steps. First, the outer-sum index is hold and increment the inner index.

Explanation:

Answer 2

This appears as the symbol, S, which is the Greek upper case letter, S. The summation sign, S, instructs us to sum the elements of a sequence. A typical element of the sequence which is being summed appears to the right of the summation sign.

Explanation: