Question

Sigma notation sum of question:

Answer 1

\[\large \sum_{k=1}^{n}k(k+1)\]

Answer 2

how do i go about evaluating it?

Answer 3

@satellite73 @myininaya @Zarkon @hartnn @phi @robtobey @radar @SmoothMath

Answer 4

Without a value for n, you can't completely evaluate it.

Answer 5

But, let me tell you what the different parts mean.

Answer 6

start with \[\sum k^2+\sum k\] and use the formulas for each

Answer 7

looking good

Answer 8

Do you understand?

Answer 9

So for this one, we would start at 1, and plug that in and get:
1(1+1) = 2

Then we would go up by one and plug that in:
2(2+1) = 6 and we would add that, so we would have
2+6 = 8

Then we would go up by one and plug that in:
3(3+1) = 12 and we would add that, so we would have
2+6+12 = 20

We would keep going until we got to n.

Answer 10

Yip. I had some knowledge on this before. I think I get how to do this, I got:\[\frac{1}{3}n(n+1)(n+2)\] as my answer