Questions tagged [homework]
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.
274
questions
32
votes
4
answers
26k
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 ...
14
votes
8
answers
5k
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:
...
9
votes
2
answers
611
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 ...
9
votes
3
answers
11k
views
I want to draw a graph using a weighted Adjacency matrix
I have a weighted adjacency matrix as follows:
...
8
votes
4
answers
1k
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 ...
6
votes
4
answers
11k
views
The Lotka-Volterra predator-prey model
I have a Mathematica assignment where we need to numerically solve a Lotka-Volterra predator-prey population equations.
$$\frac{dx}{dt}=ax-bxy,\quad\frac{dy}{dt}=-cx+dxy,$$
where $a,b,c,d\in\mathbb{R}...
6
votes
1
answer
576
views
An efficient way to translate a triple for-loop from Matlab to Mathematica
This is my first post on StackExchange, so if I violate any etiquettes, I apologize in advance. I am a senior engineering student who has been using Mathematica for a year now. For one of my classes, ...
6
votes
3
answers
525
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.
I ...
6
votes
1
answer
139
views
NumericQ exercise in Wagner
I've been thinking about this exercise in Wagner (p. 269), but I can't answer. Can you tell me?
5
votes
4
answers
510
views
Using the Tube function to create a torus from an equation for the curve
I've been searching for an answer for this for a while now, but I can't find anything that deals with using the Tube function to generate a torus from the equation of the torus.
The equation of my ...
5
votes
1
answer
317
views
How to plot trajectories of the Rossler System [duplicate]
This is my current homework problem. I have completed parts a and b, but am now stuck on part c. I'm not sure what it means by plot the trajectories with different initial conditions, nor am I 100% ...
5
votes
2
answers
177
views
How to find each internal angles of an n-sided irregular polygon
The vectors given in problem are:
p1 = {1, 2, 2};
p2 = {3, 1, 1/4};
p3 = {2, 3, 9/4};
p4 = {5, 2, 0};
p5 = {3/2, 5/4, 19/16};
Find all 5 of the (internal) ...
5
votes
1
answer
382
views
PearsonChiSquareTest: set degrees of freedom
How to set degrees of freedom for PearsonChiSquareTest?
I have this:
...
5
votes
1
answer
3k
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
3
answers
577
views
Area of volume of revolution
I want to calculate the exact area of this volume:
RevolutionPlot3D[
f[x_] = Sqrt[28 x]
, {x, 0, 21}
, Axes -> True
]
Additionally, I wish to see $x$ and $...
4
votes
2
answers
542
views
Euler-method implementation
How can I implement this pseudocode in Mathematica?
Algorithm:
...
4
votes
2
answers
380
views
How to check whether Laguerre polynomials are orthogonal?
I've got the problem with checking if Laguerre polynomials for n=1,...,10 are orthogonal.
I have to create the list of these polynomials, then create the matrix of integrals from 0 to infinity. ...
4
votes
2
answers
286
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
2
answers
597
views
Strange determinant result
I carried out the determinant of a $4\times4$ matrix in two different ways: with Laplace and without Laplace (see this attachment please).
The Laplace's rule is applied "manually" in Mathematica (I ...
4
votes
3
answers
604
views
Dot products and For-loops
I'm taking a class where we're working with matrix applications inside of Mathematica. In this case, we're analyzing senatorial votes that have been numericized so that a value of 1 corresponds to "...
4
votes
1
answer
258
views
Illustrating the central limit theorem
I'm working on this question is from Wolfram Mathematica online course. I tried my best to find the answer, still not getting it right
The question is:
Make a list of histograms of 10000 instances of ...
4
votes
1
answer
587
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....
4
votes
2
answers
215
views
4
votes
3
answers
631
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 ...
4
votes
1
answer
135
views
How can I create a randomHop function that would return certain coordinates? [closed]
I've tried to create a function that's equal to a loop containing 4 if functions, one for each integer, but the result would not show the desired outcome. How can I go about doing this question?
Write ...
4
votes
1
answer
109
views
Dynamics problem [closed]
This is school work. I do not want the problem solved for me, but I just want to know what I did wrong with my ParametricPlot.
Question:
A material point moves ...
4
votes
2
answers
330
views
Numbers to binary and back
I am struggling on how to create a function that converts a number into binary and then back. I know there is a built-in function about this BaseForm[] but I am ...
4
votes
1
answer
105
views
how to make my own `PrimeQ` function?
How can I create my own function that verifies if the number is a Prime without using PrimeQ
...
4
votes
1
answer
226
views
4
votes
0
answers
108
views
Plotting gradient and newton directions for parametric system of nonlinear ODEs
I have a bucket (system) of chemical kinetics models, a nonlinear dynamical system given by:
where kf >= 0 and kr >= 0 are the parameters. The initial conditions are A(0) = B(0) = 1 and C(0) = 0. I'...
3
votes
2
answers
630
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
2
answers
3k
views
For Loop and Sum
I am requested to do a sum of the first fifty positive even numbers by using For loop.
The For loop that I created is
...
3
votes
2
answers
4k
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 ...
3
votes
3
answers
743
views
For Loop to Sum numbers in a list
I'm asked to create a For[] loop that will sum positive numbers in a list. I am unsure of how to do this.
...
3
votes
2
answers
285
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
4
answers
549
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 ...
3
votes
3
answers
335
views
Infinite While loop
I have an exercise where I need to input a multi-digit number and evaluate the square of the sum of its digits. I am new to Mathematica and I can't figure out why I'm getting an infinite loop. This is ...
3
votes
1
answer
651
views
How do I plot a Laplace transform?
I have been looking everywhere for help on this issue and cannot find a solution that works. Here is the assignment.
I have figured out how to find the Laplace transform, but I do not know how to ...
3
votes
4
answers
455
views
Implicitly defined curve
Consider the curve $C$ defined by the equation $y\, \sin(x)+x\, \sin(y)+x+y=0$.
Find all points of the form $(8,y)$ that lie on $C$.
For each point found in part 1, evaluate the derivative $dy/dx$...
3
votes
1
answer
676
views
Adams-Bashforth method implementation code review
I have a program for Adams-Bashforth method and I want to do some tries to see if it's working properly but I don't know how to do it.
My code for AdamsBashforth is ...
3
votes
3
answers
334
views
Get a triangle’s angles from the sides
Hint: For the SSS case, you are given the 3 sides a, b, and c, and need to find the corresponding angles α, β, and γ. To find α, for example, you solve the equation ...
3
votes
2
answers
557
views
Tensor contraction
How do I let mathematica compute a tensor contraction like
$\delta_{ab}\delta_{bc}$
with an output
$\delta_{ac}$
efficiently?
I tried TensorContract and TensorReduce but they were not helpful.
...
3
votes
1
answer
2k
views
Analyze stability of equilibria using Routh-Hurwitz conditions
For an assignment, I need to analyze the stability of a system very close to equilibrium, using "Routh-Hurwitz conditions". I have already obtained the characteristic equation of my system, but I do ...
3
votes
1
answer
312
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
2
answers
215
views
Using Map to extract elements of a list
I am given this problem.
...
3
votes
2
answers
115
views
Finding the consecutive distance of n-dimensional points with Mathematica
I want to create a list of (n-dimension, average of points) with 10,000 points per n-dimension.
I can't figure out how to take the distance of consecutive points. Say in 2-dimensions, there are 3 ...
3
votes
1
answer
298
views
Tower of Hanoi list of disks on the rods
I'm currently trying to finish a program that outputs the "radius" of each disk on each rod in lists. I currently wrote this program:
...
3
votes
1
answer
320
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, ...
3
votes
1
answer
126
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
1
answer
728
views
Newton's Method
Problem statement:
I'm currently new to Mathematica and have been trying to solve this problem. I was digging around and found this code:
...