Homework questions are welcome, as long as they are asked honestly, explain the problem, and show sufficient effort. Please do not use this as the only tag for a question. Please do not add this tag to questions by other people unless they explicitly say that their question is part of their homework....

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18
votes
4answers
12k views

Finding unit tangent, normal, and binormal vectors for a given r(t)

For my Calc III class, I need to find $T(t), N(t)$, and $B(t)$ for $t=1, 2$, and $-1$, given $r(t)=\{t,t^2,t^3\}$. I've got Mathematica, but I've never used it before and I'm not sure how to coerce ...
11
votes
7answers
2k views

How to make a resizable chess board?

For some reason I need to create a chess board. I can create a chess board by following command: ...
7
votes
3answers
412 views

Generating a polynomial that's accurate to within an error of no more than 1/10^5

I'm currently stuck on a question for class that asks... "Find a polynomial p[x] that you can use to calculate 6 ArcTan[x] to ...
7
votes
2answers
422 views

Check homework integration in Mathematica

Given in my homework I have to compute (by hand) $$\iint\limits_{x^2+y^2\leq 1}(x^2+y^2)\,\mathrm dx\,\,\mathrm dy.$$ My solution so far: Let $f(x,y)=x^2+y^2$ and $K=\{(x,y)\in\mathbb{R}^2:x^2+y^2\leq ...
5
votes
1answer
225 views

PearsonChiSquareTest: set degrees of freedom

How to set degrees of freedom for PearsonChiSquareTest? I have this: ...
5
votes
1answer
597 views

How to plot the solution of a Partial Differential Equation?

My attempt. I need to solve numerically the Complex Ginzburg-Laudau Equation (CGLE): $$ \frac{\partial A}{\partial t}=\epsilon A-(1+i\beta)|A|^2A+(1+i\alpha)\nabla^2A $$ I'm using a uniform initial ...
4
votes
2answers
140 views

Use Select to filter a dataset's sublists

In the following Dataset, I want to use Select to display only rows, which contain numbers in column ...
4
votes
1answer
5k views

I want to draw a graph using a weighted Adjacency matrix

I have a weighted adjacency matrix as follows: ...
3
votes
2answers
198 views

Plotting the solutions of $y' = -\frac{\cos y}{\sin x}$

I struggle with the problem of plotting the solution of this ODE: $\qquad y' = -\frac{\cos y}{\sin x}$ I've already tried to use ContourPlot in a loop and in a ...
3
votes
2answers
228 views

Exercise using Sort

I have to order the following list according to the sum of the powers of each element of the list, using the function Sort. ...
3
votes
1answer
299 views

How can I make a pretzel shape using Bézier curves?

I am trying to make a pretzel shape,but I cannot seem to get the loops even. Eventually, I need to make the pretzel shape loop in 3D so I need to nail the 2D concept first. Here's what I have so far....
3
votes
1answer
265 views

Using single replacement rule to convert algebraic expression

I have been trying this problems for hours and cannot find any helpful clues. How can I convert $Sinh[3\theta]+Sinh[\theta]$ to a rational function of x given $2Sinh[\theta] = x-x^{-1}$ by using only ...
3
votes
3answers
127 views

Minimizing Multiple Functions

I'm trying to write a script that will minimize a given set of functions. The homework problem I've been given lists a set of dietary information, and I'm supposed to build the optimal salad based on ...
3
votes
1answer
103 views

UnitStep in Mathematica when t varies differently

How can I use the UnitStep command when I have a piecewise function $f(t)$, where $f(t)= 0$, when $|t|>4$, and $f(t)=1$, when $|t|<4$? I tried with ...
3
votes
1answer
141 views
3
votes
0answers
98 views

Writing a function to set up and solve the least squares problem

I have setup the explicit line equation for a given set of points using least-squares approximation and the knots computed below. I have tried extending the same code for use with an arbitrary degree, ...
2
votes
1answer
879 views

Using triangulation

I have been presented with 3 known points and the power densities at those points. I need to use those points to find the location of the actual antenna which is generating the signals. Power ...
2
votes
2answers
1k views

Using the epsilon tensor in Mathematica

I'm having a great deal of trouble getting started on a weekly homework assignment in Mathematica. The assignment requires we use the epsilon tensor which is apparently built into Mathematica as ...
2
votes
2answers
378 views

local variable naming & symbolic argument

I'm stuck here with my variable assignment in this scenario ...
2
votes
3answers
164 views

Finding primes that have certain property

Let S[p] denote the sum of digits of p. A prime p is said to be stubborn if none of ...
2
votes
1answer
140 views

Particle moving on curve which is the intersection of a surface and a plane

Surface z = 2 x^3 - 5 y^4 Plane z = x + y + 5 Plot A curve is formed by the intersection of the surface and the plane. ...
2
votes
4answers
318 views

Print all numbers from a sequence which don't contain the digit 7

so i have this: Cases[RecurrenceTable[{a[n + 1] == 7 a[n] + n, a[1] == 1}, a, {n, 7}], Except[7]] But i noticed that it will only exclude numbers that are 7, and ...
2
votes
1answer
207 views

Plotting and ContourPlot

Make a Plot and a ContourPlot that gives the same diagram and use ContourPlot on a quadruple ...
2
votes
1answer
404 views

Getting the 557th element of a table

Make a table with elements $\sin(\sqrt{8 n}/4) + r\, $for $n$ from $1$ to $1000$, where $r$ is a random real number between $-0.1$ and $0.1$ that is different for each value of $n$. Also make a plot ...
2
votes
2answers
593 views

Using RegionPlot3D to make a cone under restrictions

I have to plot a cone that satisfies this statement: Use the RegionPlot3D command to draw a picture of a cone with its point at the origin. The other end of the cone is a circle with radius 5 ...
2
votes
1answer
690 views

Handling ± in a set of equations

First let me post the question that I am doing: You see for wave equation y2, there is a ± sign. I know how to do + or ...
2
votes
1answer
73 views

Calculate the partial vapor pressures of a variable at xB = 0.75 based on the interpolation functions of the data

I'm having troubles in solving an exercise for an assignment in my Chemistry course. Talking about interpolations, I've already have a graph but I need to calculate the partial vapor pressures of ...
2
votes
1answer
165 views

Formatting ANOVA table and/or ParameterTable without using Grid?

Does anyone know if there is an option or function that can automatically format the output of ANOVATable and ParameterTable, ...
2
votes
1answer
249 views

Finding maximum value with LinearProgramming command

So here is a HW problem I was assigned: *Thriftem Bank is in the process of devising a loan policy that involves a maximum of $12 million. The following table provides the pertinent data about ...
2
votes
0answers
196 views

Plotting equipotentials gone wrong [duplicate]

I'm plotting the equipotential of the potential function: $$\phi(x,y,z):=\frac{1+x^{2}+y^{2}+z^{2}}{[\left(1+x^{2}+y^{2}+z^{2}\right)^{2}-4z^{2}]^{1/2}}$$ Mathematica code: ...
1
vote
4answers
614 views

Finding a number which has the same remainder when dividing certain other numbers

I am having some trouble with formulating my problem in Mathematica for this question: Is there a number greater than 1 which leaves the same remainder when it divides into 1716, 2154, and 4271? (...
1
vote
2answers
258 views

FindFit giving weird values on a logistic equation

I was trying to fit a set of data onto a logistic equation, however it ended up telling me that the initial value when $t=0$ is greater than the maximum limit, thus I am led to believe that it isn't ...
1
vote
1answer
182 views

Evaluate $\pi$ using While

I am given the following exercise: Evaluate $\pi$ using the formula $\pi = 4 - \sum_{n=1}^{\infty} (-1)^n \frac{4}{2n +1}$ with precision $\epsilon = 0.0001$. First I defined the function I need ...
1
vote
1answer
157 views

Need help defining my own rounding function

First of all: I'm a beginner with Mathematica. I'd like to define a function called Rounding which does the following: if for $x = n+a, n \in \mathbb{N}, a\in [...
1
vote
1answer
105 views

Module that prints first m positive odd integers and returns the square root of the sum of them

I am working on this problem and I feel like I've come so close. Write a module that takes as input a positive integer m, prints the first m positive odd numbers and returns the square root of the ...
1
vote
1answer
90 views

Find Values of a and b for a Limit

I am having trouble finding the values of a and b for which $\lim \limits_{x \to 0}$ $(\frac{\sin (ax) + bx)} {(x^3)}) = -32/3 $. In Mathematica I have entered: ...
1
vote
1answer
247 views

2D Markov Process

I have a homework project. I need to analyse a gambler's ruin where there are 6 possible outcomes of every wager with corresponding probabilities and payoffs and the gambler may vary the wager (say ...
1
vote
3answers
524 views

Sketch a cone and its base

A cone is the union of a set of half-lines that start at a common apex point and go through a base which can be any parametric curve. Show that the graph of z = ( x ^2 + 4y ^2)^(1/2) is a cone. What ...
1
vote
2answers
245 views

GPA calculation from a set of randomly generated marks obtained

So, this is a homework question posed by my teacher: "A student has 10 courses. Find the ceiling value of the obtained marks and corresponding grade according to the following data Print the result ...
1
vote
1answer
63 views

Calculating extrema of a given function on a geometrical region

I've never used Mathematica before. Now I have to figure out, for one of my classes, how to find the max and min of the function $f(x,y)=x^3+2\ xy$ over the triangular region of the plane with ...
1
vote
1answer
78 views

Plotting a table with varying step sizes

how can I plot the below green curve? Is there any way I could manipulate the step sizes? This is my current code: ...
1
vote
1answer
114 views

How to do predicate logic in Mathematica

I'm trying to formalize and analyze the following reasoning: All equilateral triangles are isosceles triangles. Some triangles are not equilateral triangles. Therefore some triangles are not ...
1
vote
1answer
463 views

Frequency of elements in a list (merging tally data) [duplicate]

I've got a list in the format of list={{a,1},{a,1},{b,1},{c,1},{b,1}} And I want it to "compress" into a list of pairs ...
0
votes
3answers
455 views

Creating simple procedure for The Least-Square $m^\text{th}$ Degree Polynomials

I am CS major, taking Computational Numerical Analysis course. Instructor gave us freedom of choice, we were allowed to use anything or any computer language we picked, I picked Mathematica.This is my ...
0
votes
3answers
1k views

Solving One Equation with Two Variables

I am trying to solve an equation with two variables. It is the last step in the process of using the method of undetermined coefficients to solve a nonhomogeneous differential equation. The equation ...
0
votes
1answer
136 views

Plotting Graph of Zeno paradoxes

Zeno Paradoxes is about a Greek Heroes Archilles having a race with tortoise. the tortoise given a head start distance. Greek heroes Archilles have constant speed ...
0
votes
2answers
128 views

I have the roots; how can I find an equation that they will satisfy?

I have two solutions; I want is to find an equation that these solutions satisfy using mathematica. The solutions are $x= \frac{{(26-k)}^2}{26}$ and $y= \frac{{k}^2}{26}$. I know by hand computing ...
0
votes
1answer
66 views

Poisson point distribution

The probability of n telephone calls received at an exchange in a time frame (t_i, t_f ) is given by the Poisson point distribution: ...
0
votes
2answers
128 views

recurrence equation, result members don't contain the number 5 [closed]

print the first 5 members of the array a[n+1]=3*a[n]+7 which don't contain the number 5. a1=6. so a[2]=3*6+7=25, but 25 has the number 5 so we go to a[3]. a[3]=25*3+7=82 <--- this is OK... and ...
0
votes
2answers
209 views

Least Square Fitting

stuck on a mathematica assignment and could really use some help. A) Fit a function with the shape log(Y) = a0 + a1log(U) to the datapoints (log(Ui), log(Yi) with an least square fitting. Show this ...