Heres the question:
I did this part since its simple algebra. .
Then the second part i'm stuck.
ii.) Hence write an expression in terms of n for
to n. Where it starts r = 1
Okey, so, method of differences.
I start by putting in r = 1
Then r = 2
Then r = n-1
Then r = n
Then r = r + 1
So then you add them all. Some cancel and im left with
Then i simplify and i get
And this is incorrect for the answer is
Thankyou for any help you can offer.
How do i do all these maths things to make it easier to read?
EDIT: Nvm i found the tutorial . I'll edit this with it now.