Questions tagged [equation-solving]
Questions on the analytic and numerical equation solving functions of Mathematica (Solve, Reduce, NSolve, FindRoot, DSolve, RSolve, etc.).
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Finding an increasing or decreasing function
I have a problem where I am given the derivative of a function, asked to graph it, then state where it is increasing or decreasing using Mathematica.
f'(x)=(x^2-3^x)/2x 0<x<4
I've tried the line ...
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Solving a large number of coupled non-linear equations
I would like to numerically have a solution of the Gross-Pitaevskii equation for an impurity coupled with a 1D weakly interacting bosonic bath, given by:
\begin{align}
i\frac{\partial \phi_0(x,t)}{\...
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Find the function for a decision variable
I'm currently trying to find the equation for a decision variable from a total profit equation using Mathematica. From what I've read, I can use the solve function to do this. Here's a example i found:...
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Checking the sign value of the derivatives of a complicated function
Consider the following function:
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Issues in solving a differential equation for a modified matrix
Following program works fine as it gives a solution to the differential equation here
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Solve function not returning the same output when it should
I'm trying to obtain an equation describing the intersection points of an arbitrary hyperbola with an ellipse centered at the origin. If I restrict the hyperbola to not have any horizontal translation,...
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Solving and plotting roots of a non polynomial equation with parameters
In Mathematica 12, I want to find the roots r of this equation in terms of the parameters M and Q, then plot r versus Q for some values of M.
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I have a problem with this code because it is time invertible symmetric but it is not working
I have this code I want to check for a numerical solution. I get the same shape. The function $y$ is an invertible in time so I plot $y[x]$ and $p[t]$. The $p$ function should decrease but it isn't ...
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Trying to extract the real part of a real big and may complex number
I have this order 7 polynomium:
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transport modeiling:I wish to find out volume of Heavy good vehicles [closed]
does anyone know how can I find out volume of heavy good vehicles if I only have data of total volume of vehicles and their respective speed
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Mathematica solve with conditions on constants differ from replace
I have been trying to solve some complicated linear equations in Mathematica, with variables $y_{i}$, and constants $a, f_{j}$ where $0\leq j\leq10$. I only care about the case where $\sum_{i=1}^{10}...
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Finding kernel of a set of polynomial functions
I have a list of polynomials fi[x_] and polynomial fractions qi[x_] (with i as an iterator) ...
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Numerical and analytical solutions do not agree [closed]
Hi everyone could anyone have look why this code is not running?
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Why is there a difference between the results using DirichletCondition and directly given boundary condition?
The simulation code
(The code)
TH = 800; TL = 300; U = 1000; J = 1;
[Alpha]p[x_] := 1.483110^-3 - 1.390510^-5 T[x] + 5.396410^-8 (T[x])^2 - 8.808810^-11*(T[x])^3 + 5.061810^-14 (T[x])^4;
[Kappa]p[x_]...
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