Question

Summation
Evaluate these summations.

a) N(E)k=1 (k-k^3)
b) N-1(E)k=1 (k^2/N^2)

Note that (E) is the summation symbol.

Not sure how to do these. Help would be appreciated

Answer 1

hey m not sure i understand..r the terms on the right the expression for the kth term??

Answer 2

do we have to evaluate the sum of the series whose term is k-k^3????clarify and i cn help

Answer 3

sorry it's all squashed together, didn't notice!
there are two questions:

a) N (E) k=1 (k-k^3)
b) N-1 (E) k=1 (k^2/N^2)

where N = natural numbers and (E) is the summation symbol The N and N-1 for the questions are on top of the summation symbol and the k =1 are below the symbol. The (k-k^3) and (k^2/N^2) are on the right sides of the summation symbol.

Answer 4

u can use the equation tab to write it in mathematical format

Answer 5

ugghh it keeps squashing together - but a) and b) are separate questions

Answer 6

N(N+1)/2 + [N(N+1)/2]^2

Answer 7

thats a)

Answer 8

as for b)
(N-1)(N)(2N-1)/6N ^2

Answer 9

\[\sum_{k=1}^{N}(k-k^3)\]

Answer 10

yes uzma that's the correct format for a)

Answer 11

and b?????

Answer 12

\[\sum_{k}^{N-1}(k^2/N^2)\]

Answer 13

i gave d answers

Answer 14

Yes that's the correct one for b)
him1618, thanks for your help :) and uzma too :)

Answer 15

no prob

Answer 16

did u understand the solution?

Answer 17

Yes, thank you :)

Answer 18

welcome:)

Answer 19

wht tym is it there at ur place?

Answer 20

9:02pm

Answer 21

where r u?

Answer 22

new zealand

Answer 23

k...

Answer 24

N(E)K=1(K-K^3)
(E)1/1-K^2=1/N
N=1-K^2
K=1
N=0

Answer 25

what sort of followup is this kihaga???

Answer 26

Yes! that is Honorata kihaga