Question

write down an expression, in terms of n, for the nth term formula of the sequence?
0,3,8,15,_____

Answer 1

@experimentX @dpaInc @ParthKohli

Answer 2

its not common?

Answer 3

0,3,8,15, ...
every term is of 3+2(n) more than the previous term

Answer 4

bro, how do u get it? are there any methods? please try to help?

Answer 5

where do iget the general formula for this?

Answer 6

It would be (n^2+3n-4)/2.

Answer 7

how do u get it/

Answer 8

should be n(n+2)

Answer 9

Use the second difference formula:
a+d(n-1)+1/2(n-1)(n-2)c
where a=first term,
d=difference of first two terms
c=second common difference

Answer 10

wow...i never came across this...where did u get this?

Answer 11

The internet! :D I forgot the website though.

Answer 12

how do u simplify this
1/2(n-1)(n-2)c?

Answer 13

(n^2-3n+c)/2

Answer 14

Do not replace 'n'. Just put 2 in place of c. Since it is the second common difference. 0--3 is 3| 3--8 is 5| The difference of 3 and 5 is 2.

Answer 15

do u have a webste for this, where did u search it?

Answer 16

I lost the link to the website I found it. But you can go through this one:
http://www.skoool.co.za/studynotes/maths/id635.htm
It has a few examples.

Answer 17

Oh ... i didn't know they were called quadratic sequence and have formula ...

Answer 18

HAHA! You know it now. No worries! :D

Answer 19

it is (n^2-1) thanks alot @emcrazy14 for your method...:DDDD, and @experimentX u too for trying to help me:)