The [application] tag is meant for questions about applications of mathematical concepts and theorems to a more practical use (e.g. real world usage, less-abstract mathematics, etc.)

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760 views

Optimisation of a rectangles area under a function curve

I have a questions asking for the dimensions of the rectangle with the largest area that has two bottom corners on the x axis and two top corners on the curve $y=12-x^2$. I have plotted the curve and ...
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3answers
144 views

Differentiation problem solving

I have a question which I'm unable to provide much working for as I'm not sure how to start it. A metal sphere is placed in seawater to study the corrosive effect of seawater. If the surface area ...
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1answer
332 views

Transpose a square matrix code

I know it's not programming area , but I think it's more related to math. I have the following function: ...
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1answer
55 views

represent a Toeplitz matrix in a array

I need to represent a $n \times n$ Toeplitz matrix in a $2n - 1$ array. I need to create a function that gets the $(i,j$) index of the matrix, and return the value in the $2n -1$ array. I having a ...
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3answers
287 views

Does “Big Data” Have a Ramsey Theory Problem?

I'm erring on the side of conservatism asking here rather than MO, as it is possible this is a complex question. "Big Data" is the Silicon Valley term for the issues surrounding the huge amounts of ...
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1answer
513 views

What are some applications of Trigonometry?

I have always been curious, what are some practical applications of Trigonometry? You can use it anywhere you see an angle, a triangle, or a circle. But I can't keep from wondering. Where and how? I ...
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1answer
94 views

How do I caclulate the probability of hash collisions?

I have a 10Gb file and the entire file is overwritten with random data every day. Afterwards, I divide the data into blocks and hash each block to generate a fingerprint. I am trying to choose an ...
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3answers
1k views

Applications of Calculus II to the real world

A lot of my calc II students are asking me what are the real world applications of what we are studying in Calc II (right now we are studying methods of integrations, so of course one of the ...
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2answers
46 views

What is the meaning of dimensions/units in mathematical equations?

In highschool I've always been taught the dimensions on the left hand side of the equation should always be equal to the dimensions of the right hand side, because we can't compare apples and oranges ...
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1answer
123 views

Mathematics for Graduate Political Science

I'm preparing to attend graduate school for political science here in Canada and I'm having something of a crisis. Midway through my degree program I chose to drop my first love (English) to focus on ...
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2answers
268 views

Does variance do any good to gambling game makers?

People always like to evaluate the variance, but is there any way for variance to be interesting to the gambling game makers? In another word, what is a pratical gambling game that involving some ...
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1answer
89 views

When does variance fail to meet its purpose in mathematical statistics? [closed]

It have shown in a lot of both math and statistics book, however, When the books define the variance, it doesn't give much attention to math based theoretical background, i wonder if some formula that ...
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2answers
99 views

Standard Normal Distribution to Normal Distribution

Given function f() which returns a random value from a standard normal distribution, is it possible to define a function g(mu, sigma) which returns a random value from a normal distribution with a ...
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1answer
62 views

Certainty that one has found all of the socks in a pile

Suppose that I have a pile of $n$ socks, and, of these, $2k$ are "mine." Each of the socks that is mine has a mate (so that there are $k$ pairs of my socks) I know $n$, but not $k$. Assume that all ...
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1answer
60 views

Related problems with ladder

A ladder AB of length 2a and weight w is inclined to a smooth horizontal ground(A) at an angle $\theta$ and rests against a smooth vertical wall(B). The centre of gravity G of the ladder is ...
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0answers
182 views

Application of Compass-and-straightedge construction

Nowadays with computers, Compass-and-straightedge construction doesn't look useful from my point of view. Probably I am just too narrow-minded, So I'm just curious, could anyone tell me any ...
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0answers
60 views

Present-day uses of quaternions [duplicate]

"Everybody knows" that quaternions are not used for the purposes for which they were originally intended. They are, however, used in computer graphics, and perhaps in astrogation. Besides that, what ...
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1answer
884 views

Unexpected Practical Applications of Calculus

Calculus shows up in a lot of places in the world. Specifically, here are three areas where I see it used the most: Optimization problems. Anything involving rates of change (e.g. velocity ...
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21answers
4k views

What are some examples of mathematics that had unintended useful applications much later?

I would like to know some examples of interesting (to the layman or young student), easy-to-describe examples of mathematics that has had profound unanticipated useful applications in the real world. ...
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2answers
95 views

What is the simplest $\Bbb{R}\to\Bbb{R}$ function with two peaks and a valley?

What is the simplest $\Bbb{R}\to\Bbb{R}$ function with two peaks and a valley? I have a set of points in $\Bbb{R^2}$ and I would like to fit a curve to the points, the points approximately lie on a ...
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0answers
33 views

Estimate the number of Local Minima

I am asking this question about local minima, but actually I started by trying to find the global maximum/minimum over a compact set, of a smooth function (the objective). The function has a random ...
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0answers
116 views

Applications of identity theorem to physics

Holomorphic functions have the property that they can be uniquely analytically continued to (almost) the entire complex plane. So, just by knowing how the function behaves at a teenie-weenie open disc ...
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2answers
159 views

What is the difference between the words chord, tangent in (a) and (b)?

(a) If a function $g$ is continuous on the closed interval $[u,v]$, where $u<v$, and differentiable on the open interval $(u,v)$, then there exists a point $c$ in $(u,v)$ such that ...
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3answers
584 views

Modelling with exact differential equations?

I'm teaching some very elementary differential equations to engineering students, and their constant question to me is "What's the use of this?" or alternatively "Where would we use this?" Now, I'm ...
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1answer
172 views

Graph (or Group) in Astronomy

Is there an application of graph theory (or group theory) in astronomy. If there is, refer me some references.
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199 views

Applications of matroid theory.

I am considering learning about matroid thoery. I would like to know what the applications of matroid theory are before (if they exist). Regards
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1answer
191 views

Problem related to tangents and normals of a curve.

I 've been trying the both sums, while first one I've no clue how to start about in the second one I a getting stuck. [1] The equation of the normal at any point $\theta$ on the curve $x=a ...
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0answers
574 views

Which is better, odd/even Hamming codes or extended Hamming code?

Is there a common way of naming or distinguishing between these two kinds of SECDED Hamming code? For now, I'm calling them "the odd+even Hamming code" and "the extended Hamming code". All the ...
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1answer
156 views

Applications of higher powers of trigonometric functions

I am after a reference (book, papers etc) about the practical applications of trigonometric functions raised to higher powers. An example is one that I have been using in my own studies: $\cos^4 ...
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2answers
583 views

Converting realtive humidity and temperature to an absolute value

I'm a software developer (although math isn't my strong point). I've developed a device to monitor/control my clothes dryer by monitoring the intake air's humidity & temperature, and the exhaust's ...
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3answers
245 views

What is the definition of an extremum of a function?

In calculus extremum is a common topic, but I don't understand what it is. What is the use of this extremum, especially in practical life?
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1answer
235 views

advice before i embark on my graduate studies in applied math

I'll be pursuing my graduate studies in applied math this fall. I'm hoping to gather advice in order to help me somewhat plan my courses as well as provide insight as to what is realistic or not. i ...
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0answers
113 views

simplified Linear programming model with time constraints

Based on my other question, here is a simpler hypothetical exercise that isolates that time constraint issue all together: A farmer has 1000 ha forest that is already at a mature age assumed to be ...
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0answers
93 views

Applications of a theorem of Cartier and Gabriel

In a representation theory course I took we stated and proved the following Theorem due to Cartier and Gabriel: Theorem: Suppose $H$ is a cocommutative Hopf algebra over a field $k$ such that $ ...
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2answers
314 views

Applications of integrals of rational functions of sine and cosine

I earlier asked this question about conformal equivalence of flat tori with embedded tori. In the ensuing thread the integral $\displaystyle\int\frac{dx}{R+\cos x}$ occurred. If I'm not mistaken, it ...
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2answers
349 views

How can I, as a future mathematician, contribute most to Smart Grid research?

After I've finished my Master's degree in mathematics, I too want to use my powers for good. One endeavour I consider good is the pursuit of the design and implementation of a Smart Grid which will, ...
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0answers
119 views

Calculate half life of esters

I'm trying to calculate the level of testosterone released from different testosterone esters. Here are some graphs of testosterone levels after single injections of 250mg of each ester. Testo U ...
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3answers
546 views

Uses of the incidence matrix of a graph

The incidence matrix of a graph is a way to represent the graph. Why go through the trouble of creating this representation of a graph? In other words what are the applications of the incidence matrix ...
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1answer
59 views

Show that if $f,g\in\mathcal{S}_r (E;F)$ and $f(v,v,…,v)=g(v,v,…,v), \forall v \in E $ then $f=g$.

Give $E, F$ vectorial spaces , where $\mathcal{S}_r (E;F)$ is the vectorial space the all applications r-linear symmetrics$f$, this is, the all applications $f:E \times E \times....\times E ...
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1answer
92 views

What is the best shaped blanket for my bed? (minimizing average work done in pulling it up when it falls off)

When my blanket is hanging off the bed, it's difficult to pull it up again. The more that hangs off, the harder it is; as we learn in calculus, pulling up the first half of the way is three times ...
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2answers
115 views

Name for grid system

Is there a name for a type of grid you might find in Battleship? Where coordinates don't relate to points on a grid but rather the squares themselves?
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62 views

Applied Probability with Four Disjoint Subsets.

I have a rather longwinded question, so please bear with me! A number of employees conduct duties at company X. Each type of employee meets by department 4 times yearly. Occasionally, a ...
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2answers
46 views

rate of change of quantities

the rate of an expanding rectangle is increasing at a rate of 48 cmsq/sec. The length of the rectangle is always equal to the square of the breadth. At what rate is the length increasing at the ...
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4answers
82 views

Find the equation of the tangent to the curve

Find the equation of the tangent to the curve $\sqrt X + \sqrt Y = a\;$ at the point $\left(\dfrac {a^2}{4},\dfrac {a^2}{4}\right)$ I don't know how to find $\dfrac {\mathrm dy}{\mathrm dx}$ in ...
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0answers
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Physical interpretation of Laplace transforms

One may define the derivative of $f$ at $x$ as $\lim\limits_{h\to0}\cdots\cdots\cdots$ etc., and show that that has certain properties, but it also has a "physical" interpretation: it is an ...
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2answers
90 views

Recommendations for website/journal/magazine in applied mathematics

Which website/journal/magazine would you recommend to keep up with advances in applied mathematics? More specifically my interest are: multivariate/spatial interpolation numerical methods ...
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1answer
80 views

Portfolio which replicates given payoff

Consider the following payoff function: $$p(S_T) = \begin{cases} 0 & \text{if } S_{T} \leq 70 \\ S_{T}-70 & \text{if } S_{T} \in (70; 100] \\ -S_{T}+120 & \text{if } S_{T} \in (100; 120] ...
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512 views

Applications of Banach Algebras and Operator Algebras

I am trying to learn operator algebra theory (I am tempted to start with Douglas' "Banach Algebra Techniques in Operator Theory"). One aspect that I am curious about is whether there are significant ...
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2answers
120 views

What topics to include on a first course in number theory

I need to teach a course in elementary number theory next academic year. What topics should be included on a first course in this area? What is best order of doing things? The students have a minimum ...
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2answers
221 views

Constructing bivariate pdf from polar coordinates

I'm working with a radar that gives me range and angle for each of its plots/outputs. The radar has a fixed range resolution of 20m, and an angular resolution of 2 degrees. This means that the ...