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We are an online community that gives free mathematics help any time of the day about any problem, no matter what the level. You will have to register before you can post. To start viewing messages, select the forum that you want to visit from the selection below.
HallsofIvy
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Yesterday,
23:47
MarkFL
started a thread
Compute The Limit
in
Challenge Questions and Puzzles
Compute the following limit: \lim_{n\to\infty}\left(\sqrt{\int_0^1 \left(1+x^n\right)^n\,dx}\right)
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0 replies | 2 view(s)
Yesterday,
18:51
HallsofIvy
replied to a thread
9.4.5 Identify the equilibrium values
in
Calculus
Okay, 3, 4, and 5 are equilibrium values because: when y= 3, y'= (3- 3)(3- 4)(3- 5)= 0 when y= 4, y'= (4- 3)(4- 4)(4- 5)= 0 when y= 5, y'= (5-...
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4 replies | 67 view(s)
Yesterday,
01:48
MarkFL
replied to a thread [SOLVED]
What type of mathematical function is this? Thanks :)
in
Pre-Calculus
We could likely model this with a function of the form (which comes from Newton's Law Of Cooling): f(t)=c_1e^{-kt}+350 Since we know $f(0)=70$,...
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1 replies | 50 view(s)
Yesterday,
01:01
MarkFL
replied to a thread
trigonometric inequality challenge
in
Challenge Questions and Puzzles
My solution: Consider the objective function: F(A,B,C)=\sin(A)+\sin(B)+\sin(C)-\cos(A)-\cos(B)-\cos(C) Subject to the constraint: ...
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3 replies | 97 view(s)
February 25th, 2017,
23:35
MarkFL
replied to a thread
9.4.5 Identify the equilibrium values
in
Calculus
Let's look at the behavior of the solutions near the equilibrium solution $y=3$. Suppose we have: y(0)=2.9 Then we see: y'<0 And for:
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4 replies | 67 view(s)
February 25th, 2017,
09:15
HallsofIvy
replied to a thread
9.4.5 Identify the equilibrium values
in
Calculus
Why would you "assume" that? Are you clear on what an equilibrium solution is? An "equilibrium" position is one that does not change, such as a...
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4 replies | 67 view(s)
February 24th, 2017,
11:34
MarkFL
replied to a thread
Hi - Passionate educator looking to help
in
Introductions
Hello and welcome to MHB, Jesse! (Wave) I removed the link to your email address, as that shouldn't be public, and people can just as easily...
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3 replies | 80 view(s)
February 24th, 2017,
11:28
MarkFL
replied to a thread
Linear Algebra Conditions
in
Linear and Abstract Algebra
There's no need to link to the commercial site you used. Thanks! :D
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3 replies | 93 view(s)
February 24th, 2017,
00:26
MarkFL
replied to a thread
Sequence question
in
Pre-Algebra and Algebra
Let's find the $p$th term. I think what I would do is set: \frac{n(n+1)}{2}=p Now solve for $n$... n(n+1)=2p
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1 replies | 51 view(s)
February 23rd, 2017,
22:15
MarkFL
replied to a thread
Physics 1-D Kinematics
in
Other Advanced Topics
Perhaps you meant how can we derive this formula. Let's begin with the definition of average acceleration: \overline{a}=\frac{\Delta v}{\Delta...
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4 replies | 66 view(s)
February 23rd, 2017,
20:43
MarkFL
replied to a thread [SOLVED]
A tank contains 200 gal of fresh water
in
Differential Equations
I made a mistake in my above post...the IVP should be: \displaystyle \d{F}{t}=2-\frac{5F}{4(50-t)} where $F(0)=0$. So, this leads to: ...
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7 replies | 120 view(s)
February 23rd, 2017,
16:33
MarkFL
replied to a thread [SOLVED]
A tank contains 200 gal of fresh water
in
Differential Equations
I would let $F(t)$ be the amount of fertilizer in the tank at time $t$. From the problem statement, we get the following IVP: ...
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7 replies | 120 view(s)
February 23rd, 2017,
15:01
HallsofIvy
replied to a thread
Sum of infinite series
in
Calculus
This is \sum_{n=0}^\infty \frac{(-1)^n}{(2n!)}\left(\frac{\pi}{4}\right)^{2n} Compare that to the power series for cos(x), \sum_{n=0}^\infty...
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2 replies | 60 view(s)
February 23rd, 2017,
14:51
HallsofIvy
replied to a thread [SOLVED]
A tank contains 200 gal of fresh water
in
Differential Equations
Let X(t) bet the amount of fertilizer, in lbs, in the tank at time t, in min, with t= 0 when they begin pumping the solution in. Initially the tank...
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7 replies | 120 view(s)
February 23rd, 2017,
14:31
MarkFL
replied to a thread
Physics 1-D Kinematics
in
Other Advanced Topics
I don't follow...it's already in the form we want to give us the acceleration. :D
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4 replies | 66 view(s)
February 23rd, 2017,
14:28
MarkFL
replied to a thread
Physics 1-D Kinematics
in
Other Advanced Topics
The kinematic formula you want is: \overline{a}=\frac{v_f^2-v_i^2}{2\Delta x}
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4 replies | 66 view(s)
February 23rd, 2017,
02:40
MarkFL
replied to a thread
New User Interface For Embedding Desmos Graphing Calculators In Your Posts
in
Announcements
Our goal is to make MHB stand out as much as we can from our competitors by offering features you just don't see anywhere else. If we were to package...
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3 replies | 111 view(s)
February 23rd, 2017,
02:35
MarkFL
replied to a thread
Tapatalk...
in
Chat Room
Personally, I don't think Tapatalk is ready for vBulletin, much less sites using $\LaTeX$. From what I've gathered, many vBulletin admins refuse to...
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4 replies | 89 view(s)
February 23rd, 2017,
01:29
MarkFL
replied to a thread
Tapatalk...
in
Chat Room
I'd be happy if Tapatalk didn't lazily bypass most vBulletin PHP plugin hooks. (Giggle)
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4 replies | 89 view(s)
February 22nd, 2017,
16:25
HallsofIvy
replied to a thread
Line y = (x/2) + 3
in
Pre-Calculus
Reflecting a point (a, b) about the line y= x gives the point (b, a). That is, it swaps the two coordinates. Given that y= (x/2)+ 3, x/2= y- 3 and...
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5 replies | 148 view(s)
February 22nd, 2017,
08:47
HallsofIvy
replied to a thread
Rings Generated by Elements - Lovett, Example 5.2.1 ... ...
in
Linear and Abstract Algebra
Suppose \{\frac{k}{2^n}|k,n\in Z\} were not the smallest ring containing \frac{1}{2} and all integers. That is, there exist some ring, S, that is...
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5 replies | 114 view(s)
February 22nd, 2017,
08:37
HallsofIvy
replied to a thread
How to change the subject when exponential is involved
in
Business Mathematics
Well, you probably could (I won't try to do it) rearrange the equation so the solution can be written in terms of the "Lambert W function" (defined...
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4 replies | 121 view(s)
February 22nd, 2017,
04:08
MarkFL
replied to a thread
242t.9.1.15 Use Euler's method to calculate the first three approximations
in
Calculus
Your solution to the given IVP isn't correct...we are given: \d{y}{x}=9x^8e^{-x^9} where y(0)=8 \int_{y(0)}^{y(x)}\,du=\int_0^x...
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1 replies | 65 view(s)
February 21st, 2017,
23:42
MarkFL
started a thread
New User Interface For Embedding Desmos Graphing Calculators In Your Posts
in
Announcements
Hello, MHB Community! (Wave) We are pleased to announce a new method for embedding Desmos calculators in your posts, which we hope you will find...
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3 replies | 111 view(s)
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February 25th, 2017
22:50 -
karush
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Re: 9.4.5 Identify the equilibrium values
by
HallsofIvy
Why would you "assume"...
February 23rd, 2017
19:14 -
Opalg
clicked Thanks for this post:
Re: Sum of infinite series
by
HallsofIvy
This is...
15:48 -
Umar
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Re: Sum of infinite series
by
HallsofIvy
This is...
15:43 -
karush
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Re: A tank contains 200 gal of fresh water
by
HallsofIvy
$\tiny{9.3.15}$ A tank...
14:58 -
MarkFL
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Re: A tank contains 200 gal of fresh water
by
HallsofIvy
$\tiny{9.3.15}$ A tank...
February 22nd, 2017
19:58 -
Peter
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Re: Rings Generated by Elements - Lovett, Example 5.2.1 ... ...
by
HallsofIvy
Suppose...
19:55 -
Farmtalk
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Re: Line y = (x/2) + 3
by
HallsofIvy
Reflecting a point (a,...
18:09 -
greg1313
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Re: Line y = (x/2) + 3
by
HallsofIvy
Reflecting a point (a,...
18:07 -
MarkFL
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Re: Line y = (x/2) + 3
by
HallsofIvy
Reflecting a point (a,...
11:43 -
MarkFL
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Re: Rings Generated by Elements - Lovett, Example 5.2.1 ... ...
by
HallsofIvy
Suppose...
08:42 -
HallsofIvy
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Re: Rings Generated by Elements - Lovett, Example 5.2.1 ... ...
by
johng
You have to understand...
08:34 -
HallsofIvy
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Re: help
by
Joppy
Hi, welcome to the...
February 21st, 2017
15:27 -
MarkFL
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Re: Terminology
by
HallsofIvy
More generally,...
February 20th, 2017
23:44 -
caffeinemachine
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Re: Terminology
by
HallsofIvy
More generally,...
19:57 -
woof123
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Re: linear relationship question
by
HallsofIvy
Equivalently, any linear...
03:43 -
Farmtalk
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Re: Solution to equations
by
HallsofIvy
Hi everyone, What is...
February 19th, 2017
17:16 -
rebo1984
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Re: Solution to equations
by
HallsofIvy
Hi everyone, What is...
10:44 -
MarkFL
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Re: Solution to equations
by
HallsofIvy
Hi everyone, What is...
February 18th, 2017
16:37 -
karush
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Re: 231.14.88 3d surface
by
HallsofIvy
Strictly speaking, it is...
13:21 -
Euge
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Re: 231.14.88 3d surface
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HallsofIvy
Strictly speaking, it is...
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