Formula: ∑ AI (I = 1 ...), where ∑ stands for continuous addition, right-handed writing formula, and subscript writing range. ∑ is called continuous plus sign, which means: a1+a2+...+an = n.
∑ (summation symbol)
English name: Sima.
Chinese name: Sima. (capital σ, lowercase σ)
The eighteenth Greek letter. In Greek, if the last letter of a word is lowercase sigma, what should it be written as? This letter is also called final sigma(Unicode: U+03C2). In modern Greece, this number stands for 6.
Capital σ is used for mathematical summation symbols, such as ∑Pi, where i= 1, 2, ..., t, which is the sum of P 1+P2+ and ...+angle. Lowercase σ is used for statistical standard deviation. Both the с of Cyrillic alphabet and the S of Latin alphabet are derived from Sigma.
It also means summation, which means ∑ j =1+2+3+…+n.
The usage of ∑:
Where I stands for the lower bound, n stands for the upper bound, and k starts from I and goes all the way to n, all of which add up.
∑ i can also be expressed as the sum of I, which is a variable.
∑∑, sigma, the Greek letter (pronounced sigma) stands for "sum" in mathematics, for example:
∑pi, I is 1, 2, ..., t.
Is to find the sum of p 1+p2+ and ...+angle.