The sum symbol ∑ is the capital of the Greek letter Sigma, which means that all the numbers on its right, here, 1/n2, are added together. The "n= 1" below ∑ means that we start with n= 1. According to the convention, n is a positive integer that increases in turn.
The ∞ above ∑ means "infinity", telling us to add these numbers until forever. So it's the same as the infinite series we saw before, just put it another way: for n= 1, 2, 3, …, add the term 1/n2.
Extended data
The sign of the summation sign ∑ is as follows:
(m is any integer less than n)
Example:
Where i= 1 is subscript, 4 is superscript, and 0.5i is algebra. Then sum the values of I separately.
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