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 ...

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17
votes
4answers
9k 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 ...
7
votes
3answers
342 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
6answers
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: ...
6
votes
1answer
341 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
158 views

PearsonChiSquareTest: set degrees of freedom

How to set degrees of freedom for PearsonChiSquareTest? I have this: ...
5
votes
1answer
185 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 ...
3
votes
1answer
4k views

I want to draw a graph using a weighted Adjacency matrix

I have a weighted adjacency matrix as follows: ...
3
votes
1answer
240 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
81 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
94 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 ...
2
votes
1answer
835 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
834 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
331 views

local variable naming & symbolic argument

I'm stuck here with my variable assignment in this scenario ...
2
votes
3answers
150 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
4answers
222 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
167 views

Plotting and ContourPlot

Make a Plot and a ContourPlot that gives the same diagram and use ContourPlot on a ...
2
votes
2answers
270 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
167 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
69 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
114 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
308 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 ...
2
votes
1answer
125 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
388 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
193 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
145 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
129 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
217 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
197 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
160 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
71 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
79 views

MathematicaPolarPlot Question [closed]

Using this as an example PolarPlot[{1,Sin[3 θ]},{θ, 0, 2 π}] Now consider the family of polar curves r=a+Sin[3 θ] as we vary ...
1
vote
1answer
340 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
416 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
534 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
2answers
116 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
118 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
2answers
173 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 ...
0
votes
1answer
488 views

Calculating orbital period for the logistical map [closed]

I have the following MatLab code ...
0
votes
1answer
105 views

AstronomicalData not including units?

I like using mathematica to do my physics homework, and AstronomicalData is useful for that, but it doesn't seem to work properly with units. [the question is, at ...
0
votes
3answers
114 views

Defining a function which displays odd numbers? [closed]

Define a function that takes as input an integer n and returns as output the product of the first n odd numbers., i.e., 1 · 3 · 5 · · · 2n − 1. Evaluate your function at 1, 2, 3 and make sure you get ...
0
votes
2answers
178 views

Fraction of fibers that have failed

I have the following to set into mathematica. Assume a stress(sigma) applied on a specimen which has a number of fibers within it. All fibers that have a strength less than the applied stress should ...
0
votes
2answers
119 views

Testing the Erdos square free conjecture

Can someone please answer these two parts of my homework assignment? Adding an explanation would be appreciated! a. Test the Erdos square free conjecture for $n <= 30000$. You should use ...
0
votes
2answers
74 views

Write the equation as a polynomial in x and extract the coefficient of x^2 [closed]

I need help solving this problem. Thank you. (a*x^2 + b*x*Sin[y] + c*Sin[y])^2 + (a*Sin[y]^2 + b*x)^3 Write the above as a polynomial in x and extract the ...
0
votes
1answer
77 views

Using Plot and Piecewise to graph a roller coaster

I am graphing a roller coaster using Piecewise and Plot commands on Mathematica. I have the first 2 Piecewise functions and would like to add a loop to the end of it. Here is my initial graph: This ...
0
votes
1answer
68 views

Fourier series of the odd extension of a function [duplicate]

Using Mathematica to make a plot, I noticed that the interval it's defined over must be changed in order to do the Fourier series. How do I change the interval to be on an interval of $[-{\cal l}, ...
0
votes
1answer
83 views

Replace notebooks and pens with Mathematica? [closed]

I use Mathematica for math homework/learning. I'm trying not to use it for solving equations I should be solving by myself to get homework done faster and not learn anything. I think I can (and ...
0
votes
1answer
420 views

How to solve a problem in relative motion?

I have a project due tomorrow that I have been struggling with for a month. I am utterly stumped, any help would be appreciated. The problem is: There is a ferris wheel, 30m in radius, set 80m ...
0
votes
0answers
59 views

Error with ND Solve [on hold]

I am new to Mathematica, and I am having some issues solving a homework problem of a differential equation. Here is the code: ...
0
votes
0answers
5 views

Problem with Integration using substitution [migrated]

OK, so here is a question from integration that I recently stumbled upon. Evaluate $I =\int\cos^3\theta\sin\theta\,d\theta$ Now here's how I tried to solve it first; $Substitute \cos\theta = t$ ...