• Today, 15:25
It's a "rite of passage" for calculus students. (Smile)
3 replies | 22 view(s)
• Today, 07:20
l will now attempt to, explicitly, complete the demonstration that Df(a) v = \sum_{ 1 \le j \le n } v_j D_j f(a) \ \ \ \ (v \in \mathbb{R}^n ) ...
4 replies | 62 view(s)
• Today, 01:11
Here is an attempt to show Df(a) v = \sum_{ 1 \le j \le n } v_j D_j f(a) \ \ \ \ (v \in \mathbb{R}^n ) Now we have ... Df(a) v =...
4 replies | 62 view(s)
• Today, 00:59
Thanks Country Boy ... ... appreciate the help ... Peter
4 replies | 62 view(s)
• Today, 00:54
Thanks GJA ... that was really helpful ... Still reflecting on what you have said ... Thanks again ... Peter
2 replies | 60 view(s)
• Yesterday, 23:26
Here is this week's POTW: Let $ABCD$ be a convex quadrilateral with $\overline{AB}=\overline{AD}$. Let $T$ be a point on the diagonal...
0 replies | 34 view(s)
• Yesterday, 23:21
No one answered this weeks POTW...my solution follows: (a) Apply conservation of angular momentum (subscripts of $R$ pertain to the rod, while...
2 replies | 149 view(s)
• Yesterday, 13:34
$$\int_1^{\infty}\frac1x \, dx$$ does not converge. If you were to try to get an antiderivative, the only candidate is $\ln|x|$, so formally, you'd...
3 replies | 69 view(s)
• Yesterday, 07:38
I am reading "Multidimensional Real Analysis I: Differentiation" by J. J. Duistermaat and J. A. C. Kolk ... I am focused on Chapter 2:...
4 replies | 62 view(s)
• Yesterday, 06:50
I am reading "Multidimensional Real Analysis I: Differentiation" by J. J. Duistermaat and J. A. C. Kolk ... I am focused on Chapter 2:...
1 replies | 40 view(s)
• Yesterday, 00:31
\frac{5}{4}\cdot\frac{4}{3}=\frac{5}{3} :)
14 replies | 222 view(s)
• February 20th, 2018, 23:10
MarkFL posted a visitor message on Peter's profile
Sometimes editing a thread title is an issue, but the issue is with vBulletin. If you ever want to change a thread title, and can't, just let me know...
• February 20th, 2018, 22:24
Thanks again Krylov .... BUT ... just a comment on D&K's proof .... I have to say that D&K's proof of Hadamard's Lemma though valid, is not...
3 replies | 77 view(s)
• February 20th, 2018, 21:57
I am reading "Multidimensional Real Analysis I: Differentiation" by J. J. Duistermaat and J. A. C. Kolk ... I am focused on Chapter 2:...
0 replies | 25 view(s)
• February 20th, 2018, 21:26
I am reading "Multidimensional Real Analysis I: Differentiation" by J. J. Duistermaat and J. A. C. Kolk ... I am focused on Chapter 2:...
2 replies | 60 view(s)
• February 20th, 2018, 20:41
Thanks Krylov, ... followed your advice and obtained the result ... Thanks again ... Peter
3 replies | 77 view(s)
• February 20th, 2018, 17:09
I'm going to walk through this problem, using your substitution...let's begin with: I=\int_{0}^{\Large\frac{3\pi}{4}}\int_{0}^{\pi}\int_{0}^{1}...
14 replies | 222 view(s)
• February 20th, 2018, 16:30
Where did the $\cos(\theta)$ come from?
14 replies | 222 view(s)
• February 20th, 2018, 16:28
I was simply taught that a linear function has no concavity...just recalling from memory. :)
20 replies | 259 view(s)
• February 20th, 2018, 16:24
Let's look at an example that more clearly demonstrates the statement regarding concavity isn't always true. Consider: H(x)=\ln(x+1) And so: ...
20 replies | 259 view(s)
• February 20th, 2018, 15:58
Perhaps there are differences in terminology...I was taught that a function is concave up on an interval when its second derivative is positive, and...
20 replies | 259 view(s)
• February 20th, 2018, 15:47
Indeed, and is why I resorted to looking for a function satisfying the given criteria, that is not concave up on the given interval. :)
20 replies | 259 view(s)
• February 20th, 2018, 15:41
You want to reverse the limits of integration, because of the negative sign in the differential resulting from your $u$-substitution (I don't know...
14 replies | 222 view(s)
• February 20th, 2018, 14:37
Suppose $h(t)=c$, where $0<c$...what is $H(x)$?
20 replies | 259 view(s)
• February 20th, 2018, 07:17
Oh! OK ... get the idea ... Thanks ... Peter
2 replies | 59 view(s)
• February 20th, 2018, 07:04
I am reading "Multidimensional Real Analysis I: Differentiation" by J. J. Duistermaat and J. A. C. Kolk ... I am focused on Chapter 2:...
3 replies | 77 view(s)
More Activity

### 37 Visitor Messages

1. Happy birthday, caffeinemachine!
2. Yes caffeinemachine, I have a different solution of my own. I would have posted it along with johng's yesterday, but I was in a hurry, as I needed to get other things done. I might post it later today.
3. Thank you! It's been a bit hectic, what with moving to Kansas, and all. But I did have a great birthday.
4. Hi caffeinemachine. Very sorry that this is happening. Could you make a thread in our feedback forum describing what is happening when you get a moment? We will try to fix it ASAP.
5. My interests lie in dispersive wave equations and geometric analysis. You have a pretty interesting combination: combinatorics and geometry. So will you do combinatorial geometry or geometric combinatorics?
6. Hi caffeinemachine! I just wanted to wish you a happy birthday, and I hope you're having a great time.
7. Hey, just wanted to thank you. I didn't know the command \widehat existed until I saw you using it in your question about modules. Hope you get an answer, haha.

Best wishes.
8. Happy Birthday, my friend!
9. Hi AK,

I wish you luck, happiness, health and safety today, tomorrow and beyond...

As you look back on yesterday, may your memories be warm ones. As you celebrate today, may your heart be filled with happiness and joy. As you look ahead to tomorrow, may your deepest hopes and dreams come true for you!

I wish that for every extra candle on your cake, you receive an extra reason to smile. Happy Birthday to you!
10. Hi, I'm currently traveling but will get back to you later today. Thank you for your patience!
Showing Visitor Messages 1 to 10 of 37
Page 1 of 4 123 ... Last
Page 1 of 4 123 ... Last

#### Basic Information

Date of Birth
April 13, 1991 (26)
Biography:
I obtained a master's degree in mechanical engineering in May 2014.
Then I went on to join a master's programme in mathematics and obtained a master's degree in July 2016. I am currently a first year PhD student in mathematics. I love fountain pens and am a die hard fan of the Prince of Persia 2008 video game.
Location:
India
Interests:
Mathematics, Taekwondo.
Occupation:
Student
Country Flag:
India

#### Statistics

Total Posts
780
Posts Per Day
0.36
Thanks Given
564
1,103
1.414
##### Visitor Messages
Total Messages
37
Most Recent Message
April 13th, 2017 22:36
##### General Information
Last Activity
February 5th, 2018 00:17
Last Visit
February 4th, 2018 at 10:19
Last Post
February 4th, 2018 at 02:49
Join Date
March 10th, 2012
Referrals
2
Referred Members
cupofcoffee, hersh

### 19 Friends

1. #### AckbachOffline

Indicium Physicus

2. #### anemoneOffline

Paris la ville de l'amour

3. #### ArenholtOffline

MHB Apprentice

4. #### BacteriusOffline

MHB Journeyman

5. #### Bruce WayneOffline

MHB Apprentice

MHB Master

7. #### FantiniOffline

MHB Craftsman

8. #### Fernando RevillaOffline

MHB Journeyman

9. #### JamesonOffline

Администратор

10. #### johngOffline

MHB Craftsman

Showing Friends 1 to 10 of 19
Page 1 of 2 12 Last

#### February 4th, 2018

Ranks Showcase - 1 Ranks
Icon Image Description

Name: MHB Topology and Advanced Geometry Award (2016)
 Issue time: January 9th, 2017 14:38 Issue reason: