Mathematics

this maybe a little silly...but i have here a debate... Is algebra and calculus necessary for a comman man to live in the society??? That is, are they used in the pratical life?? I vote that they are not necessary for a common man.. What about you...

Paper: Author [Jordan Micah Bennett] (myself): advertising links removed by moderator ... I am new here. Please express your thoughts.

OK this has been annoying me, I'm sure it's relatively simple and I'm just missing something... like the power of thought... show that: [math] \sum_{l=0}^{n-1}(2l+1)=n^2 [/math]

Hey all, I was browsing through our math book the other day, and I came upon an interesting question. Say you have a table with a diameter of 0.6m, and on that table a square meter-by-meter tablecloth. One corner of the tablecloth is hanging over by half a meter, and another by 0.3 meters. By how much are the other corners hanging over? I came up with 0.5 and 0.3 meters, but I'm not sure I'm right. Can anyone verify? Thanks in advance, Gabe

http://img693.imageshack.us/img693/3950/calcw.png http://rapidshare.com/files/325308950/operators.xlsx.html http://www.filehosting.org/file/details/91934/operators.xlsx Above is an image of a spreadsheet and two link to the spreadsheet itself. My thoughts are based on the way that multiply can even if not the most efficient way of performing the calculation can be thought of as repeated add, and power repeated multiplication. Although there are differences beyond that and other calculations just as simple and multiply that don't have names. Columns C and D of the spreadsheet show the descriptions of increment and decrement. Thease add and subtract 1. I do…

y = psinx + qcosx passes through the points (0,3) and (pi/4,0). Find the values of p and q. Using formula on the coordinates i've got y = 3 + 12x/pi so psinx + qcosx = 3 + 12x/pi but then where? only 2 identities i need for this course is sinx/cosx = tanx and (sinx)^2 + (cosx)^2 = 1 but i cant see how i can use these

Hi, i have a very simple question (easy to state, i meant...) -Can someone explain, in the simplest possible way, why the complex numbers were chosen as a basis for the infinite series of the Zeta function? (in other words: why did Riemann build up his hypothesis of his Zeta function's non-trivial zero rational parts, in the idea of numbers which are partly imaginary too, ie x+iy)? I ask because, ideally, i would not want to spend huge amounts of time making a connection which probably is quite simple in regards to examining the hypothesis itself. I can suspect that Riemann formed the hypothesis as a (particular type of) series based on complex numbers due to the abili…

Does there exists any two distinct numbers a and b, such that a^b=b^a ?

Hello everyone I'd just like to known if the formulas below are correct. Normally I wouldn't post such a short/maybe dumb question, but since Wolfram|Alpha won't generate these formulas, which are, according to me, somewhat obvious, I'd just like to know if there are correct. [math]a^n-b^n=(a-b)\cdot \sum_{i=1}^n{\left(a^{n-i}\cdot b^{i-1}\right)}[/math] [math]a^n+b^n=(a+b)\cdot \sum_{i=1}^n{\left((-1)^{i-1}\cdot a^{n-i}\cdot b^{i-1}\right)}[/math] Thanks. Function

Alright, so I think I solved this algorithm, I call it the shrink ray, I got the idea from Minions. Pretty much with any number of A-B in binary, you can reverse engineer A and B from C alone knowing how many 1's and 0's there are for A and B. For example: 1010 A (two 1's, two 0's) -0101 B (two 1's, two 0's) -------- 0101 C Note: I've only tested the condition for A>B, not negative numbers Now you reverse engineer A and B from C, you know C is 5 and A and B are bigger, so you can have A=6 B=1, A=7 B=2, A=8 B=3, A=9 B=4, A=10 B=5, A=11 B=6, A=12 B=7, A=13 B=8, A=14 B=9, A=15, B=10. Now with all these conditions available, the only set that holds true w…

I posted this on PF but it didn't get very far: Suppose {a[n]} is an increasing sequence and whenever m divides n, then a[n] = a[n/m] + d where m is a positive integer and d is a real number. Show that a[n] = Θ(lg n). I can show that a[n] = O(lg n). All I need to do is show that a[n] = Ω(lg n). This is where I'm stuck. Any hints?

As the equation says A+B=C, let's say I add 7(A) and 9(B) to get 16©, is it possible to reverse engineer 7 and 9 by only knowing 16? It can be in binary or anything. I'm trying to get the value for A and B with C=16 and without knowing what A and B are An idea would be to mesh the binary bits together like, A=0111, B=1001, C=0111 1001, but that makes C bigger to have a value of C=64+32+16+1 = 113. I need to make this value smaller then the previous two numbers, which should only contain 4 bits, so the maximum value would be 1111 which is 15 Reverse half adders?

I know the value of dn/dt (e.g. dn/dt = 123). a3 = 345 / n2 Is there any way to calculate da/dt?

I read that learning to use an abacus can help with one's own mental arithmetic... anyone experienced this? And any suggestions of a good abacus (type) to buy? Thanks in advance..

Hello, I've been reading a bit about Gödel's Incompleteness Theorem. On this video ( ) of a talk at Google, the speaker mentions that there are true statements that cannot be proven. My question is: how can a statement be true and not be proven, in other words, how can we be absolutely certain that it is true if we cannot prove it? Hope this is clear. Thank you, David

hi; I need some scientist's experiences ,my specific questions are below ; 1) do such journals care that from which (type of) journals our article's citation-references have been done (the equivalent question is whether will it be better us to cite and give references from just that journal we would submit our articles?) 2) how the ranks are being given according to this website : http://www.scimagojr.com/journalrank.php 3) does this mean that if one journal is "open access" ,then it will not be well known journal and I see we are able to make show all open access journals via using item on the website (given above) , but let think we found any journal…

Lets say that we have the set [math]P = { 2, 3, 5, 7, ... }[/math], where [math]P[/math] is the set of all prime numbers ... The series [math]P_1 + P_2 + P_3 + ...[/math] does it converge or diverge ..? [math]\sum_{P_i \in P} P_i \; = \; ?[/math]

about the highest and lowest of function, if we get the lowest value of function like sinus and cosinus ( exmaple ) , od minus them we get the medium of function, but the doing it on back, we maybe get the lowest and hightest of this function and if we get y = 2x + 1, and change it to 2x - 1, we can do 2x + 1 / 2x - 1, and dont know if it will make something

I saw this and thought of it as a pretty cool "Eureka!" moment. Anyone care to comment? Also, do you know of a similar situation where the "problem" is originally/naturally viewed one way, but superior scientific insight results in a solution that's different? source

hey guys could i get a hint at how to do this problem please? i just can't quite work out what my first step should be,.... Thanks -Sarah

i get the basic abs value inequalities e.g. abs(1+x)>3 etc... how do we solve in general for abs valued inequalities like this?? abs(x+1)+abs(x+3)+5>abs(4+x) etc.... im alittle confused. thanks in advance.

5 km/h*sec -Is how my textbook gives equation for acceleration which confuses me because the way I understand, it should be: 5 km/h/sec the textbook equation would read - five kilometers per hour each second while mine would read - five kilometer per hour per second Is there any difference between them that I am missing, and do you think my professor would take points off if i do it later way? I am in a course where I teach myself and turn my work in, and semester has not even began yet so i can't ask directly and this is just a litlle thing that wont leave my mind

I was thinking about the quote "Nothing is impossible" and it brought up the idea of carrying out a specific task the same, but with a different set of restrictions or rules applied to that task needed to be done. Yes, certain things are impossible because of the rules of physics and the rules of mathematics, but some how we find a way to accomplish that task another way. I find it interesting how this can be done even within a different set of rules and restrictions. So, it got me thinking that these tasks being done in a different set of restrictions can be generalized by a function that if you have found the process of completing a task within one set of restrictio…

Accuracy up to how many decimals...........? 32 + 42 = 52 9 + 16 = 25 1.(3/4)2 + (4/4)2 = (5/4)2 0.752 + 12 = 1.252 0.5625 + 1 = 1.5625 2.(3/5)2 + (4/5)2 = (5/5)2 0.62 + 0.82 = 12 0.36 + 0.64 = 1 O.K. Fellas, let’s notice a difference here. 3.(3/3)^2 +(4/3)^2 = (5/3)^2 1^2 + 1.3^2 = 1.6^2 1 + 1.69 = 2.56 Difference => 2.69 – 2.56 = 0.13 Accuracy =>0.13/2.69=.048 4.(3/3)^2 +(4/3)^2 = (5/3)^2 1^2 + 1.33^2 = 1.66^2 1 + 1.7689 = 2.7556 Difference => 2.7689 – 2.7556 = 0.133 Accuracy => 0.133/2.7689 = 0.00…