Can anyone tell me what this symbol is?

[markraz]

Can anyone tell me what this symbol is? is this PI? 3.14?? thanks in advance

 

[Romsek]

It is a capital pi but it means that you take the product of the indexed terms.

For example \(\displaystyle \prod \limits_{j=1}^n j= n!\)

 

[ksdhart2]

The "capital pi" symbol is the multiplicative analogue of the sigma operator. That is to say:

\(\displaystyle \sum\limits_{k = 1}^{n} k = 1 + 2 + 3 + \cdots + n = \frac{n(n+1)}{2}\)

But:

\(\displaystyle \prod \limits_{k=1}^{n} k = 1 \times 2 \times 3 \times \cdots \times n = n!\)

 

[markraz]

The "capital pi" symbol is the multiplicative analogue of the sigma operator. That is to say:

\(\displaystyle \sum\limits_{k = 1}^{n} k = 1 + 2 + 3 + \cdots + n = \frac{n(n+1)}{2}\)

But:

\(\displaystyle \prod \limits_{k=1}^{n} k = 1 \times 2 \times 3 \times \cdots \times n = n!\)

thanks !!!

 

[pka]

Can anyone tell me what this symbol is? is this PI? 3.14?? thanks in advance

Using the classical Greek alphabet the capital \(\displaystyle \Pi\) corresponds to the English P.
So it is natural to use it for Product. Thus \(\displaystyle \prod\limits_{k = 1}^9 {{{(x + 1)}^k}}\) is the product of nine factors.
Just as \(\displaystyle \Sigma\) corresponds to S, it is used to denote sums.