How do I calculate the sum? (Discrete Math)

[hushed quarry]

I'm not really sure how to approach this. I understand how to read a summation, but since there is no upper limit, I'm not sure what to do

[hushed quarry]

Am I on the right track with this?

[hollow drift]

The upper limit is i=n

[hollow drift]

Yes, if n1=1, n2=2, and so on

Also, as a hint, if you know the summation of n^2 and n, you can substitute those here for the answer

[hushed quarry]

So I know that i^2 = [n(n+1)(2n+1)]/2. Is that what you mean by substituting it?

I know you can also split summations that are being added. But I'd assume I can't split them in substraction?

[hollow drift]

Summation of n^2 is equal to that, and yes

[hollow drift]

You can

Addition is just substracting negatives

[hushed quarry]

is this the answer?

[hollow drift]

Yes!

[hushed quarry]

Nice, thank you!

.close

[hollow drift]

.close

[past ivy]

Solved

Post marked as solved by @hushed quarry.

Use .unsolved if this was a mistake.

Solved

Post marked as solved by @hollow drift.

Use .unsolved if this was a mistake.