Tab Content
• Today, 03:13
Here is this week's POTW: ----- Find the exact value for the real root of the equation $x^3+3x-2=0$. ----- Remember to read the POTW...
0 replies | 27 view(s)
• Today, 02:59
Congratulations to the following members for their correct solution::) 1. kaliprasad 2. lfdahl Honorable mention goes to cmath123, as he has his...
1 replies | 107 view(s)
• Yesterday, 18:23
Euge replied to a thread [SOLVED] How to prove continuity? in Analysis
Yes.
4 replies | 59 view(s)
• Yesterday, 18:19
Euge replied to a thread [SOLVED] How to prove continuity? in Analysis
It's a great idea, but for this argument to work, $f(c)$ needs to be positive. It's possible to avoid cases by setting $\epsilon = \frac12\lvert... 4 replies | 59 view(s) • Yesterday, 04:59 Joseph A. Gallian, in his book, "Contemporary Abstract Algebra" (Fifth Edition) defines an irreducible element in a domain as follows ... (he also... 0 replies | 34 view(s) • Yesterday, 04:23 Thanks for the help johng ... But i am still a bit puzzled ... I think we have to show that \{ \frac{k}{ 2^n} \ | \ k.n \in \mathbb{Z} \} is... 3 replies | 51 view(s) • Yesterday, 02:29 MarkFL replied to a thread 231.14.88 3d surface in Calculus Multiplying through by$9+6x-8y$and distributing the$26$, we obtain -x^2-y^2+z^2=156x-208y+234 -x^2-156x-y^2+208y+z^2=234 ... 3 replies | 53 view(s) • February 16th, 2017, 23:12 I am reading Stephen Lovett's book, "Abstract Algebra: Structures and Applications" and am currently focused on Chapter 5 ... I need some help... 3 replies | 51 view(s) • February 15th, 2017, 20:29 You have two points on the graph, so you can compute the slope as follows: m=\frac{\Delta y}{\Delta x}=\frac{y_2-y_1}{x_2-x_1} Then, you can... 2 replies | 58 view(s) • February 14th, 2017, 23:47 Yes, the derivative of the function evaluated at the$x$-coordinate of the tangent point will give you the slope$m$of the tangent line. :) 4 replies | 89 view(s) • February 14th, 2017, 23:18 The first derivative of a function gives you the slope of the tangent line, not the tangent line itself. Thus,for some function$f(x)$, the tangent... 4 replies | 89 view(s) • February 14th, 2017, 22:17 Let's try your substitution of: u=x+9\implies du=dx I=\int_9^{18}\frac{(u-9)^3}{u^2}\,du By the binomial theorem: ... 1 replies | 47 view(s) • February 14th, 2017, 18:27 Okay, I see what you are doing now. Yes, you can do it but I find it to be a bit confusing since you are (temporarily) giving x a value. Since you... 3 replies | 63 view(s) • February 14th, 2017, 16:48 You aren't setting x to be anything. You have two equations: 1 = 3A - 3B 0 = 5Ax + 5Bx which has to be satisfied by all x. So the second... 3 replies | 63 view(s) • February 14th, 2017, 12:31 Just to follow up, we left off with: 8-\frac{15000}{x}=5 Arrange as: 3=\frac{15000}{x} Multiply through by \frac{x}{3}\ne0: 2 replies | 100 view(s) • February 12th, 2017, 22:13 Thanks for the help, Euge ... Appreciate your assistance ... Peter 2 replies | 61 view(s) • February 12th, 2017, 18:16 Euge replied to a thread I made it shorter in Analysis Hi sarrah, Why is $$\|P_1(t)\| \le \int_0^t e^{\|A\|(t - \tau)}\|B\|e^{\|A\|\tau}\,d\tau?$$ It appears you used a Minkowski type... 2 replies | 84 view(s) • February 12th, 2017, 18:03 Hi JGalway, To prove the result formally, I suggest using the principle of mathematical induction. 2 replies | 52 view(s) • February 12th, 2017, 17:57 Hi Peter, Yes, that's correct. 2 replies | 61 view(s) • February 12th, 2017, 17:28 Welcome, hksuraj! (Wave) What have you tried? Please show your thoughts on this problem, even if you only have the definitions. 1 replies | 59 view(s) • February 12th, 2017, 03:00 I have been thinking around the definition of a unit in a ring and trying to fully understand why the definition is the way it is ... ... Marlow... 2 replies | 61 view(s) • February 12th, 2017, 00:21 Yes, we use$\LaTeX$powered by MathJax, which is what you'll find on most other math sites. The only difference is, unlike other sites, we provide... 3 replies | 105 view(s) • February 11th, 2017, 23:14 Yes, that's exactly the reason. 1 replies | 56 view(s) • February 11th, 2017, 10:06 Euge replied to a thread [SOLVED] Do the integrals converge? in Analysis I think you were missing my point. In your other post, the cosine is multiplied by a damping function, making the integral absolutely convergent.... 11 replies | 239 view(s) • February 11th, 2017, 08:06 Euge replied to a thread [SOLVED] Do the integrals converge? in Analysis Direct comparison requires the integrand to not change sign, right? The cosine changes sign over$[0,\infty)\$, so direct comparison will not do with...
11 replies | 239 view(s)
More Activity

### 16 Visitor Messages

1. Hi Deveno ... ... Hope you return to MHBs soon ... you are sadly missed ...

Peter
2. Hi Deveno ... haven't seen you for a while ... hope all is well with you ...

Best regards,

Peter
3. Hi Deveno,

work has taken me out of the state of Tasmania and into regional Victoria ... about 150kms outside Melbourne ...

Should re-establish broadband links and get some time in a day or so ...

Thanks as always for you help ...

Peter
4. Hello and welcome back to MHB, Deveno!

We are happy to see that you have returned, and we look forward to your continued participation here!

On Behalf Of MHB's Staff,

anemone.
5. Good answers on Peter's questions, and well-given exercises too. Unfortunately though I wouldn't be able to check Peter's work on the matrix algebras. Every ring is commutative to me
6. Thanks a bunch, I'll see if I can play through your ideas.
7. Hello, David, what d'you think of the group theoretic analogy of galois theory I have posted in the abstract algebra forum? Can this thing be arrow-theoretically generalized to categories too?
8. I'm a little late but congratulations on 1k posts! Really happy to have you at MHB and here's a toast to the next 1k.
9. excellent respond to the "how do you add and subtract measurements" thread. i would not have had the energy to go through all of that step by step like that.
10. Hey nice color change!
Showing Visitor Messages 1 to 10 of 16
Page 1 of 2 12 Last
Page 1 of 2 12 Last

#### Basic Information

Biography:
i am uncountably finite
Location:
Interests:
i used to like eno b4 he went bald
Occupation:
erstwhile designer of some sort
Country Flag:
United States

#### Statistics

Total Posts
1,964
Posts Per Day
1.07
Thanks Given
419
4,364
2.222
##### Visitor Messages
Total Messages
16
Most Recent Message
January 22nd, 2017 20:47
##### General Information
Last Activity
October 30th, 2016 18:09
Last Visit
October 9th, 2016 at 10:16
Last Post
September 16th, 2016 at 20:08
Join Date
February 15th, 2012

### 14 Friends

1. #### alane1994Offline

MHB Craftsman

2. #### AlexmahoneOffline

MHB Craftsman

3. #### anemoneOffline

Paris la ville de l'amour

MHB Master

5. #### FantiniOffline

MHB Craftsman

6. #### jacobiOffline

MHB Apprentice

7. #### MarkFLOnline

Pessimist Singularitarian

MHB Master

9. #### PranavOffline

MHB Craftsman

10. #### Rido12Offline

MHB Journeyman

Showing Friends 1 to 10 of 14
Page 1 of 2 12 Last