Tab Content
• Today, 11:16
I'm not sure if there is a name for it. This is just something I thought of. My thinking was, to relate the integral to the limit definition of...
3 replies | 100 view(s)
• Today, 00:02
You wound up with $x^2\sin(x)$ on the RHS before integrating, but it should be $x\sin(x)$. :)
2 replies | 54 view(s)
• Yesterday, 19:23
When you multiply through by $\mu(x)$, you should have: \frac{d}{dx}(\sin(x)y)=2 And then integrate: \sin(x)y=2x+c_1 ...
2 replies | 36 view(s)
• Yesterday, 09:31
I'm stepping in for Ackbach temporarily until he returns. Here is this week's POTW: ----- Suppose $D$ is a compact domain of $\Bbb R^3,$ $F : D... 0 replies | 43 view(s) • June 19th, 2018, 21:45 Hi Another, Let$A_n := \int_0^\infty x^ne^{-x}\ln(x)\, dx$for$n = 0,1,2,3,\ldots$. We desire to find$A_0$. By integration by parts, ... 3 replies | 100 view(s) • June 19th, 2018, 21:18 Here is this week's POTW: ----- Find a general solution of the nonlinear differential equation$$\left(\frac{dy}{dt}\right)^{\!\!2} -... 0 replies | 46 view(s) • June 19th, 2018, 20:32 This week's problem was solved correctly by Opalg. You can read his solution below. By the quotient rule,$\phi'(z) = \dfrac{1-\bar{a}z +...
2 replies | 290 view(s)
• June 19th, 2018, 19:21
Towards the end, when you divide through by $x$, you want: y(x)=\frac{e^x}{x}+\frac{c}{x} You mistakenly divided the constant by $e^x$.
1 replies | 41 view(s)
• June 19th, 2018, 15:31
Yes, but you used it on the original ODE, not the one in standard linear form. :)
4 replies | 91 view(s)
• June 18th, 2018, 06:19
Thanks steenis ... No worries at all ... Thanks for all your help ... Peter
10 replies | 220 view(s)
• June 18th, 2018, 06:04
Thanks Steenis ... That proof seems really clear ... Will work through it again shortly... Peter
4 replies | 82 view(s)
• June 18th, 2018, 05:18
Sorry Steenis ... I don't understand you ... Can you give me a hint as to what is wrong ...? Peter
10 replies | 220 view(s)
• June 18th, 2018, 04:51
Thanks steenis ... most helpful ... Can see that the short exact sequence $0\rightarrow \text{ker } f \overset{i}{ \rightarrow}R^{(n)}... 10 replies | 220 view(s) • June 18th, 2018, 01:22 ======================================================================== Since I could not see any specific errors, I have completed the proof... 4 replies | 82 view(s) • June 17th, 2018, 12:39 MarkFL replied to a thread [SOLVED] 2.2.3 de with tan x in Differential Equations I can't imagine trying to use the internet on a telephone. I'm sorry scrolling on a telephone is such a chore...they should fix that. 8 replies | 113 view(s) • June 17th, 2018, 05:04 Peter started a thread Deveno ... in Chat Room Deveno is much missed ... especially by those who frequent the Linear and Abstract Algebra Forum ... Deveno's pedagogical abilities were as... 0 replies | 58 view(s) • June 17th, 2018, 04:40 I am reading Dummit and Foote's book: "Abstract Algebra" (Third Edition) ... I am currently studying Chapter 10: Introduction to Module Theory ...... 4 replies | 82 view(s) • June 17th, 2018, 00:59 MarkFL replied to a thread [SOLVED] 2.2.3 de with tan x in Differential Equations Are you using Tapatalk by any chance? I have code in place to let me know when posts have been edited, so I don't miss added content (it's better to... 8 replies | 113 view(s) • June 17th, 2018, 00:52 MarkFL replied to a thread [SOLVED] 2.2.3 de with tan x in Differential Equations When you multiply by$\mu(x)$, you get: \sec(x)y'+\tan(x)\sex(x)y=\sec(x)\sin(2x) This can be written as: ... 8 replies | 113 view(s) • June 16th, 2018, 23:10 Thanks Steenis ... You have shown that$R^{(n)} / N \cong M$where$N = \text{ Ker } f$... ... ... ... ... (1) ... and we have by... 10 replies | 220 view(s) • June 16th, 2018, 19:51 MarkFL replied to a thread [SOLVED] 2.2.3 de with tan x in Differential Equations -\ln(\cos(x))=\ln\left((\cos(x))^{-1}\right)=\ln(\sec(x)) 8 replies | 113 view(s) • June 16th, 2018, 19:38 MarkFL replied to a thread [SOLVED] 2.2.3 de with tan x in Differential Equations \mu(x)=\exp\left(\int \tan(x)\,dx\right)=e^{\Large\ln(\sec(x))}=\sec(x) 8 replies | 113 view(s) • June 16th, 2018, 00:29 300+300\cdot\frac{1666}{100}=300(1+16.66)=300\cdot17.66=5298 Here, we have taken 300, and added 1666% of 300 to it. However if we multiply 300 by... 6 replies | 126 view(s) • June 16th, 2018, 00:03 Thanks steenis ... but not sure if I follow .. ... but will try ... as follows ... We have an epimorphism$f:R^{(n)} \longrightarrow M\$ ...
10 replies | 220 view(s)
More Activity

### 27 Visitor Messages

1. Hey thanks Euge! Sorry couldn't reply earlier.
2. Hi Euge, I'm enjoying a quiet birthday, with just a few days to go before my wife and I go off for our annual holiday in the Canary Isles to escape some of the British winter.
3. Happy Birthday!!! Hope you had a great year and another one is to come! Thank you so much for all you do here.
4. Happy Birthday Euge!
5. Thanks, Euge!
6. Thank you, Euge! I hope you had a great weekend.
7. Thank you very much!!
8. Hi Euge!! On this special day.... I wish you happiness, health and so many good things in your life!! Happy Birthday, Euge!
9. Hey Euge, thanks. It's really an honor
10. Thank you, Euge!
Showing Visitor Messages 1 to 10 of 27
Page 1 of 3 123 Last
Page 1 of 3 123 Last

Date of Birth
January 10
Country Flag:
United States

#### Statistics

Total Posts
1,683
Posts Per Day
1.15
Thanks Given
1,825
4,311
2.561
##### Visitor Messages
Total Messages
27
Most Recent Message
April 15th, 2017 09:10
Last Visit
Today at 11:16
Last Post
Today at 11:16
Join Date
June 20th, 2014
Referrals
1
Referred Members
eric509

### 9 Friends

1. #### caffeinemachineOffline

MHB Journeyman

2. #### Chris L T521Offline

MHB Journeyman

MHB Master

4. #### MarkFLOnline

Pessimist Singularitarian

5. #### OlokOffline

MHB Craftsman

6. #### Pantaron EducatOffline

MHB Apprentice

MHB Master

8. #### Rido12Offline

MHB Journeyman

9. #### SudharakaOffline

MHB Master

Showing Friends 1 to 9 of 9
Page 1 of 3 123 Last

#### May 31st, 2018

• 20:13 - Ackbach clicked Thanks for this post: -= Hidden Content =- by Euge

Page 1 of 3 123 Last
Ranks Showcase - 8 Ranks
Icon Image Description

Name: MHB Topology and Advanced Geometry Award (2017)
 Issue time: January 21st, 2018 09:44 Issue reason:

Name: MHB Analysis Award (2017)
 Issue time: January 21st, 2018 09:42 Issue reason: Congratulations!

Name: MHB Advanced Algebra Award (2016)
 Issue time: January 9th, 2017 14:37 Issue reason:

Name: MHB Topology and Advanced Geometry Award (2015)
 Issue time: January 7th, 2016 11:09 Issue reason:

Name: MHB Analysis Award (2015)
 Issue time: January 7th, 2016 11:09 Issue reason: