Recent content by doggie_Walkes

This has stuck with me for a long time, i just can't do it. If the sequence of functions, fn(x): R+ --> R where fn(x) is defined as fn(x) = x/n if 0 is greater than and equal to x, x is less than and equal to n fn(x) = 1 if x is strickly greater than n I need to show...

I still don't get it :(

Prove that countable intersections of closed subset of R^d are closed

Ah tiny tim, I get it! thanks that's bothering for some time, can i ask one more thing of you please. How would one go about doing this? 5x2+y2 = 7z2 Deduce that the equation has no solution in intergers except fo x=y=z= 0

thanks tiny tim for replying so quickly. well I am checked the answer then its says this, "the only possiblity is that y=z=0(mod5) but then 5*x^2=7*z^2 - y^2 is divisble by 25, and so x is divisble by 5." so i get why the obly possiblity is 0mod5 but why is it divisble by 25...

Hey this is just a fun question that my teacher said. But haven't got a clue. Suppose you draw a n x n grid on a piece of paper. how many squares could you draw in the diagram? how many rectangles can you contain. Its something to do with binomial coefficients, what you guys think?

Well the problem is Prove that if x, y, z are intergers such that 5*x^2 + y^2 = 7*z^2, then x, y and z are all divisble by 5. So what I have done so far, I have worked out 1, 2 ,3 , 4, and their squared to find that. the squared intergers of any interger will end in 0,1, 4 in modulo...

Hey mark, sorry for the late reply, Im just wondering what you mean by ones' digit

It just how do i prove that b^3 +b^2 +1 does not divide by 5 Im thinking this way, cause i know that b^3 +b^2 +1 is not congruent to 0(mod5) therefore we use contradition to prove it. I am just not sure how to use contradition? or maybe I am looking at this in a completely bad...

Thanks mark. I just had a bit of another question if I could ask you ask well? It just how do i show b^3 +b^2 +1 does not divide by 5 how do i prove it. Im thinking this way, cause i know that b^3 +b^2 +1 is not congruent to 0(mod5) therefore we use contradition to prove it. I...

Hey I am just wondeirng if I have to prove a congruence, such as c^3 is congruent to d modulo 7, where d is set of {0,1 ,7} So in this problem to prove this example all I need to do is prove that it is a equivalence relation? So it is reflexsive, symmetric, and transitive? Is...

yes i do mean -1 \le z \le 1 can u help me on the question?

well if i first find the CDF of FX(x) then um, try plugging it into find the probablility of y<_y?

Just wondering if someone could help me out on a problem. i mean PDFs, not CDFs in the title. Soz Thanks in advance. <_ means greater and equal to Well, if we give Z to be a random varible with a pdf of: pdf of Z = (5/2)*z^3 if -1<_ z _> 1 0 otherwise...

This is a question from A consise introduction to pure mathematics (Martin Liebeck) Hi guys, just stuck on one problem was wondering if someone could lend me hand. Let ~ be an equivalence relation on all intergers with the property that for all "m" is an element of the set of intergers ...