# Sum of squares of even numbers

• Nov 27th 2009, 02:53 PM
erinneedshelp
Sum of squares of even numbers
What is the value of (sum of j2 where j is an element of S)
where S = {all even numbers greater than zero and less than 11}

• Nov 27th 2009, 04:21 PM
emakarov
I assume the expression is $\sum_{j\in S} j^2$ where $S=\{n\in\mathbb{N}\mid0< n<11,\ n\mbox{ is even}\}$. I don't really know what to say except that you need to know what the notations $\sum$ and $\{\dots\mid\dots\}$ mean. If you know this, you can calculate this quantity directly, without using any general formula.
• Nov 27th 2009, 04:22 PM
mr fantastic
Quote:

Originally Posted by erinneedshelp
what is the value of (sum of j2 where j is an element of s)
where s = {all even numbers greater than zero and less than 11}

2^2 + 4^2 + 6^2 + 8^2 + 10^2 = ....