Tab Content
• Today, 17:57
When I throw it at Octave online, I get: So it seems it is none of the above, but the answer $3$ is close. For reference, I have re-encoded...
1 replies | 30 view(s)
• Today, 14:20
Let $f:\mathbb R\to \mathbb R$ be a twice-differentiable function such that $f(x)+f^{\prime\prime}(x)=-x|\sin(x)|f'(x)$ for $x\geq 0$. Assume that...
1 replies | 30 view(s)
• Yesterday, 16:46
This should be fairly simple, convert 360 degrees in 18 minutes to x degrees in 1 minute. The graph shows height of a capsule above the ground in...
2 replies | 43 view(s)
• Yesterday, 12:06
Hi all, I think even we do switch to XF (is still going to happen) the time has come to make a change. We have a database of amazing content here...
1 replies | 108 view(s)
• Yesterday, 11:37
Hi all, I hope you are all safe, healthy, and not affected in a serious way by the world wide COVID-19 virus. Here in the US it has completely...
0 replies | 47 view(s)
• Yesterday, 11:34
Hey mathmari!! This is an example where Newton-Raphson can have problems if we are not careful. If we pick a starting value that is too far from...
2 replies | 41 view(s)
• Yesterday, 11:33
skeeter replied to a thread [SOLVED] Transportation calculus in Pre-Algebra and Algebra
that's my mistake ... should be 14.9. I doubled the numerator and denominator to get the coefficient of $n$ to be 1 instead of 0.5. When I decided...
10 replies | 355 view(s)
• Yesterday, 10:30
\frac{\left(x\sin\left(\pi\left(x-1\right)\right)\right)}{e^{x/9}(x-1)} The above graph shows that the function repeats its value at $x=1$ when $x$...
2 replies | 41 view(s)
• Yesterday, 09:09
skeeter replied to a thread [SOLVED] Transportation calculus in Pre-Algebra and Algebra
what does n-1 represent? in the equation I wrote in post #4, $n$ represents the number of additional freight loads
10 replies | 355 view(s)
• April 5th, 2020, 10:58
skeeter replied to a thread [SOLVED] Transportation calculus in Pre-Algebra and Algebra
I have a better idea ... explain how you derived your function.
10 replies | 355 view(s)
• April 5th, 2020, 10:37
I substituted $n=\frac 1{x^2}$, which also means that $x^2=\frac 1 n$. So we get $\Big(1 + \frac 32 x^2\Big)^{1/x^2} = \Big(1 + \frac 32 \cdot \frac... 7 replies | 232 view(s) • April 5th, 2020, 09:14 It's like this: $$\Big(1-\frac 12 x^2 + \ldots\Big)\Big(1+\frac 12 (2x)^2 - \ldots\Big)\\ =1\cdot 1 -\frac 12 x^2 \cdot 1+1\cdot \frac 12 (2x)^2 -... 7 replies | 232 view(s) • April 5th, 2020, 07:04 The series expansion of \cos x = 1 - \frac 12x^2 + \ldots. And the expansion of \frac 1{1-x} = 1+x+x^2+\ldots So:$$\frac{\cos(x)}{\cos(2x)}... 7 replies | 232 view(s) • April 5th, 2020, 01:08 Here is this week's POTW: ----- Suppose that the positive integers$x, y$satisfy$2x^2+x=3y^2+y$. Show that$x-y, 2x+2y+1, 3x+3y+1$are all... 0 replies | 180 view(s) • April 5th, 2020, 01:02 No one answered last week's POTW.(Sadface) Below is a suggested solution: The given function is the square of the distance between a point of the... 1 replies | 147 view(s) • April 4th, 2020, 12:16 skeeter replied to a thread [SOLVED] Transportation calculus in Pre-Algebra and Algebra simplified the initial cost function ...$C(v) = 1375\left(\dfrac{44.5}{v} + \dfrac{14.9}{180-v}\right)$minimum cost occurs at$v \approx 114...
10 replies | 355 view(s)
• April 4th, 2020, 09:26
skeeter replied to a thread [SOLVED] 299What is the acceleration in Calculus
$v(t) = \cos{t}+\sin{t} \implies a(t) = \cos{t}-\sin{t} \implies a\left(\dfrac{3\pi}{4}\right) = -\sqrt{2}$
4 replies | 274 view(s)
• April 4th, 2020, 04:14
This is actually a proof of (ii) $\Rightarrow$ (iii) in Lemma 3.2. So we are assuming that (ii) holds. In particular, since $\overline{ f(A) }$ is...
1 replies | 194 view(s)
• April 3rd, 2020, 15:47
I have obtained access to the full solutions manual, after contacting Wiley about it. I will not type up the solution in full, but simply note a few...
1 replies | 250 view(s)
• April 3rd, 2020, 10:39
skeeter replied to a thread [SOLVED] Transportation calculus in Pre-Algebra and Algebra
What are your units for speed, the $x$ in your cost function? I get cost as a function of speed, $v$, in km/hr ... $C(v) = 1375 \bigg$ unit...
10 replies | 355 view(s)
• April 2nd, 2020, 17:07
skeeter replied to a thread f in Calculus
don't know math ... ?
5 replies | 303 view(s)
• April 2nd, 2020, 15:47
In the mid-1990's, an electrical engineer/computer scientist by the name of Judea Pearl started to change the world by greatly improving our...
0 replies | 213 view(s)
• April 2nd, 2020, 12:25
Klaas van Aarsen replied to a thread f in Calculus
It appears the answer is: dkm Acronym for "don't kill me". Often used when somebody says something that somebody else finds really funny,...
5 replies | 303 view(s)
• April 1st, 2020, 15:04
$\newcommand{\doop}{\operatorname{do}}$ Problem: (This is from Study question 4.3.1 from Causal Inference in Statistics: A Primer, by Pearl,...
1 replies | 250 view(s)
More Activity

### 145 Visitor Messages

1. Hi
I've a question if you could help me with it, i'd be happy.

Question:
Expand and simplify the following set of brackets: f(x)=(x+2)(x+4)(x+1)

f(x)= ............ X3+………….. X2+…………………. X+11

regards
John
2. Thank you very much for the kind "Welcome" !!!
3. Hi. Thanks for the welcome. This is my first ever involvement in a forum. Not sure about the thread thing. I got a message when i first signed up that i had to reply to a thread before i posted my own? True?
4. thank you for the message I had a question regarding this website. how long does it usually take to get a response to something
5. Not to sure where to start. I have say a wire frame with 4 O/S perimeter measurements (measurements not even and is not square) 2 diagonal measurements 2 opposite points are low and the other 2 are higher I dont have the heights. My problem is I would like to find the centroid point and have the 4 new diagonal measurements to fill this in with 4 triangles of material. I want to do the Calculations in a spreadsheet as the measurements could change I think first off I need to work out the height ,work out all the horizontal measurements,work out the centroid of that then half the height and do the Pythagoras from that. I can give you my measurements that I have made up. Ive tried to do the maths in excel by flattening and find out the new bd using ac diagonal and finding the new ac using bd measurements but I was getting 2 different heights not by much 13 mm I know why but got lost. Hope you can understand where I going with this. This problem has been bugging me for years. Allan
6. how do I post my own problem I need help with?
7. Hi,

I need help for below solution

The height in inches of 10 students selected at random are as follows
61 62 62 65 66 67 68 69 69 70

on the basis of this figures is it correct to conclude that the mean height of students is 68 inches?
8. Thank you!
9. also can u pls suggest important questions of maths for class 12 2018 board for maths
10. sir i have a doubt in chapter 1 relations and functions example 23,24,25 of class 12 .please solve them boards are approaching
Showing Visitor Messages 1 to 10 of 145
Page 1 of 15 12311 ... Last
Page 1 of 15 12311 ... Last

Country Flag:
Malaysia

#### Statistics

Total Posts
3,330
Posts Per Day
1.12
Thanks Given
20,011
9,581
2.877
##### Visitor Messages
Total Messages
145
Most Recent Message
October 5th, 2019 14:40
##### General Information
Last Activity
Today 11:38
Last Visit
Today at 09:15
Last Post
April 5th, 2020 at 01:08
Join Date
February 14th, 2012
Referrals
3
Referred Members
Albert, einsnul, MarkFL

### 28 Friends

1. #### AckbachOffline

Indicium Physicus

MHB Master

3. #### awkwardOffline

MHB Apprentice

4. #### bwpbruceOffline

MHB Apprentice

5. #### caffeinemachineOffline

MHB Journeyman

6. #### Chris L T521Offline

MHB Journeyman

MHB Master

8. #### DreamWeaverOffline

MHB Craftsman

9. #### FarmtalkOffline

MHB Apprentice

10. #### Fernando RevillaOffline

MHB Journeyman

Showing Friends 1 to 10 of 28
Page 1 of 3 123 Last
Page 1 of 2 12 Last

#### April 3rd, 2020

• 11:52 - anemone clicked Thanks for this post: -= Hidden Content =- by Ackbach

#### April 1st, 2020

• 14:57 - Ackbach clicked Thanks for this post: -= Hidden Content =- by anemone

#### March 20th, 2020

Page 1 of 2 12 Last
Ranks Showcase - 8 Ranks
Icon Image Description

Name: MHB Challenges Award (2016)
 Issue time: January 9th, 2017 14:42 Issue reason:

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

Name: MHB Best Ideas Award (2015)
 Issue time: January 7th, 2016 11:10 Issue reason:

Name: MHB Challenges Award (2014)
 Issue time: January 3rd, 2015 15:31 Issue reason:

Name: MHB Challenges Award (Jul-Dec 2013)
 Issue time: January 5th, 2014 16:56 Issue reason:

Name: MHB LaTeX Award (Jul-Dec 2013)
 Issue time: January 5th, 2014 16:52 Issue reason:

Name: Secondary School/High School POTW (Jul-Dec 2013)
 Issue time: January 5th, 2014 16:48 Issue reason:

Name: MHB Challenges Award (Jan-June 2013)
 Issue time: July 1st, 2013 22:20 Issue reason: