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# General Math

- Math topics not applicable to the categories below. High-school Math
 Views: 8,499 Announcement: Two free ways to get Gold Membership! Jan17-12 Meta Thread / Thread Starter Last Post Replies Views Please post any and all homework or other textbook-style problems in one of the Homework & Coursework Questions... Feb23-13 09:23 AM micromass 1 32,496 \sum_{i=1}^{n} i is the sum of all numbers between 1 and n. I'm trying to find one for odd numbers where you need... Feb29-12 12:54 PM dodo 8 18,448 Hello. I've searched around a bit for a math forum where I could get help with this and this seems like the one I... Mar5-06 07:18 PM bobbybob 2 26,198 Does anyone know if there is a summation formula to find the sum of an expression with n as an argument in a trig... May3-09 01:44 PM Ben Niehoff 1 2,333 Hey everyone, I need some help trying to figure out how to find the summation of n \sum_{}^{\6}i^p i=0 I was... Feb28-09 12:54 AM CRGreathouse 1 1,119 Hi guys, sry if i asked a silly qns. Is the below equivalent is true??? ... Sep5-09 04:17 PM jgens 1 2,324 Hello, If we get a summation \sum_{r=a}^{b}, where a > b, how to treat this summation? Regards Jun4-09 07:47 PM Moo Of Doom 5 1,142 Is \sum_{u,v} H_{i-u,j-v}F_{u,v} the same as \sum_u\sum_v H_{i-u,j-v}F_{u,v} ? Mar11-07 06:39 PM AlephZero 3 3,029 I know this should be easy and the answer will be glaringly obvious in hindsight but my brain is fried and I can't for... Nov24-10 09:22 AM y35dp 2 1,128 I am trying to understand summation notation and there are a few inconsistencies in my head that I would like to clear... Feb9-12 07:12 AM HallsofIvy 2 1,186 Folks, I am struggling to see what is happening here particularly when ## \displaystyle \sum_{i=1}^{n-1}##... Sep14-12 01:09 PM bugatti79 2 962 Hi I have a text book which uses the notation: \sum\limits_{i\neq j}^N a_i a_j I can't find anywhere what... Jan10-14 09:44 AM SergeantAngle 3 307 How would I write the result of this in summation notation after multiplying it out? (\sum^{n}_{i=1} x_{i})^{2} Oct7-10 05:47 PM zgozvrm 3 1,292 i need to find a series of numbers up to n that will add up to kn x1 + x2 + x3+ ... + n = kn where k is a constant.... Feb22-13 08:09 PM Simon Bridge 9 967 Hello, Can we write a summation of exponentials, as a multiplication of exponentials? Regards Jun14-09 06:00 AM S_David 3 845 well, peaking is just a term I gave to a sequence that progresses normally, but when it gets to the point of... Nov11-09 10:18 PM yyttr2 0 527 Hi everybody, I am just trying to find a decent identity that relates the sum $$\sum_{k=0}^{n}a_kb_k$$ to another sum... May12-13 04:35 PM tiny-tim 6 545 Hello, Can anyone give some hints on how to solve this: \sum_{n=0}^{K-1}\frac{sin(2\pi n^2\Delta)}{n} It's just... Apr2-07 04:02 AM AlphaNumeric 3 2,541 Hello i want to know if we have a series with this equation... Sep6-12 03:29 PM mathman 6 765 Hello, i have been trying to solve a summation question for a while, and i'm not too much of an expert at the subject,... Jun20-11 02:48 AM dimension10 7 1,208 prove that: \sum_{m=0}^{q} (n-m) \frac{(p-m)!}{m!} = \frac{(p+q+1)!}{q!} (\frac{n}{p+1} - \frac{q}{p+2} ) using... Nov27-10 08:20 AM Suk-Sci 2 685 I just thought I would share this, I was about to ask you fine people how to do this when I realized the square root... Nov11-09 11:40 PM hwmaltby 7 902 \sum_{n=1}^{\infty}n^{-2}=\frac{\pi^2}{6} I'd like to know how to prove this summation. And if possible, what is... Aug13-09 10:49 AM g_edgar 2 1,021 I have the following recurrence that I am trying to come up with atleast a simplified version if not a closed form. ... Nov11-07 02:31 PM jamesvanboxtel 3 1,414 \sum_{n=0}^{\infty} \frac{2^{n+1}(n+1)t^n}{(n+2)!}=\sum_{n=0}^{\infty} \frac{2^{n}nt^{n-1}}{(n+1)!} How are the... May15-10 06:24 PM Landau 1 835 hey pf! can someone explain to me what to do if presented with an equation like this: \sum_{i=1}^{n}A_i=i is this... Jan20-14 08:29 PM joshmccraney 3 274 I have a rather simple question, but my rusty brain needs a good, swift kick-start. I start with: \sum_{i=1}^k i... Dec2-04 08:16 AM dogma 2 6,871 I need to simplify this expression and I don't know how to deal with the factorials in the sum e^{-(\lambda +... Nov28-12 11:35 AM Polymath89 4 843 My logic is flawed somewhere, but I can't figure out where or why. So I've been playing with summation a bit and... Nov30-11 02:53 PM PEZenfuego 6 2,301 (This is not a homework question!) I have no education in this kind of math yet, but I wonder how many ways you are... Feb2-07 12:45 PM disregardthat 9 8,024 kx^n = \sum_{j=1}^n ({(j-k)x^{n-j}d_j}) dj is a constant but dependent on j, i.e. independent of x. k is an integer... Dec26-13 10:27 PM Shyan 1 317 Hey all. I'm curious about something. I've ordered some books and dvds on Algebra 1, 2, and Advanced Algebra (college)... May24-09 11:49 PM symbolipoint 3 855 hi all, i'm hoping that some of you might be able to help. i'm currently in a state of perplexity and doubt. i'm... Apr19-08 11:30 AM sabbthdaylake 0 965 If one was to sum a series by grouping each two terms would that be legtimate? i.e if you have an alternating... May23-07 07:27 AM Gib Z 3 1,208 The real projective line states that there is not difference between positive and negative infinity (maybe except the... Dec13-13 08:59 PM japplepie 3 450 Hi. This is the first Topic I've posted at (the very cool) Physics Forums site so go easy on me. My English is very... Dec15-06 09:40 AM Werg22 4 1,223 How can I prove this? Suppose X is a set of 16 distinct positive integers, X=\left\{{x_{1}, \cdots ,... Oct29-07 06:08 AM Gib Z 2 1,203 I have a mathematical model which, in part, does a calculation based on the location of certain points on a unit... Jun6-12 11:05 PM theorem4.5.9 3 1,518 I'm curious if there is a way to combine sinusoids of multiple frequency into a single sinusoid? For example, I'm... Sep18-13 09:41 AM arildno 5 628 This is a very similar question to what I posted earlier. Basically I am trying to find when (x+y)6 = x6 + y6... Feb1-12 02:21 PM micromass 6 677 Can someone confirm/disprove the following: If X\subset\mathbb{P} is infinite, then \sum_{n\in X}\frac{1}{n}... Jul31-06 09:02 AM NateTG 16 3,125