You are Here: Home

# Sum of a series

Maths and statistics discussion, revision, exam and homework help.

Announcements Posted on
Find out how cards are replacing warnings on TSR...read more 03-12-2013
1. Sum of a series
Find the sum from zero to infinity of (x^(2n+1))/n!, i have managed to get this tyo equal 1+x^3(sum from zero to infinity of ((x^2)^n)/(n+1)!. BUt i am unsure how to calculate this sum.
2. Re: Sum of a series
What I would do is and from there you can recognise a common power series.
3. Re: Sum of a series
(Original post by ttoby)
What I would do is and from there you can recognise a common power series.
Can you show me how to calculate sum of the common power series?
4. Re: Sum of a series
Can you show me how to calculate sum of the common power series?
Do you recognise ?

Compare this with the power series you have.

(As a hint, in this case, it's less about "calculation" than it is about definition: a common function is defined by this power series.)
5. Re: Sum of a series
(Original post by nuodai)
Do you recognise ?

Compare this with the power series you have.

(As a hint, in this case, it's less about "calculation" than it is about definition: a common function is defined by this power series.)
e^2x?
6. Re: Sum of a series
e^2x?
No, that would be . (Also you forgot the multiplying the sum.)
7. Re: Sum of a series
(Original post by nuodai)
No, that would be . (Also you forgot the multiplying the sum.)
The only thing it looks vaugely like is cosh ?
8. Re: Sum of a series
The only thing it looks vaugely like is cosh ?
It's not cosh. Use the information you have: I presume you know that , right?

What do you need to put equal to in order to get ? So what is this sum equal to?

So, following what ttoby said in his post above, what is equal to?
9. Re: Sum of a series
xe^(x^2)!!
10. Re: Sum of a series
xe^(x^2)!!
Correct! Unless that's a double factorial...
Last edited by olipal; 07-05-2012 at 18:09.
11. Re: Sum of a series
(Original post by olipal)
Correct! Unless that's a double factorial...
Haha

## Step 2: Register

Thanks for posting! You just need to create an account in order to submit the post
1. this can't be left blank

this is what you'll be called on TSR

2. this can't be left blank

never shared and never spammed

3. this can't be left blank

6 characters or longer with both numbers and letters is safer

4. this can't be left empty
1. By completing the slider below you agree to The Student Room's terms & conditions and site rules

2. Slide the button to the right to create your account

You don't slide that way? No problem.

Last updated: May 7, 2012
Study resources