Tagged Questions

Questions on the analytic and numeric equation solving functions of Mathematica (Solve, Reduce, NSolve, FindRoot, DSolve, RSolve, etc.).

353 views

DSolve returns a “wrong” solution

This wrong solution exists from mma9 to mma10.1: ...
38 views

How to solve a system of equations which includes vectors? [duplicate]

I'm starting to wonder if this is something that mathematica just can't do? I thought something like this might work: ...
345 views

Solving a two variable two equation trig expression

I am trying to use Solve to get what two angles (A and B) are in a problem I have. ...
64 views

Reducing a system of vector equations

I'm trying to solve a system of vector equations. I know this is solvable since I've done it myself by hand (I reduced it to solving the root of a quartic anyway). I'm trying to do it in Mathematica ...
124 views

Stability analysis of transcendental equation (stability crossing curves)

I am working with a non-linear delay system with three scalar delays. After taking the Laplace transform of the linearized system, the characteristic function is a transcendental equation with three ...
606 views

Solving an equation takes too long

I am trying to solve the following equation func[a, b, c, d, e] == 0 where ...
45 views

Defining a function in terms of a solution returned by Solve

The title is a little ambiguous, but I didn't know how else to put it. What I'm trying to do is solve a system of equations ...
93 views

Use FindRoot to get the root with minimum imaginary part

For example, define test[z_] := Cosh[0.5132928614530164 z] + 0.5934823341977118 Sinh[0.5132928614530164 z] And ...
70 views

List manipulation performance or how to make independent list copy

I have a task to solve some system of equations with NSolve and print graph of it, depends on parameters. Something like this (maybe it is not a good example and does not always have a solution, but ...
105 views

645 views

Finding intersections of two parametric curves

I am dealing with the root finding of two parametric data curves (data below). I have already checked Parametric Interpolation of 2D data, which I found useful for plotting, though it is not adequate ...
283 views

I'm trying to reproduce the following plots: As described by this blog entry: Synchrotron radiation As you can see in the linked article, the task is essentially to make a ...
71 views

NSolve running for ever

I have troubles running NSolve for my physics problem. I am new to Mathematica, which is why I might be missing some key solutions. I have the following function with the variables: ...
91 views

Solution Branch Switching of Quartic

Im using a closed form solution for quartic equation. In the quartic equation, there are parameters that are being varied and therefore the solution changes depending on these parameters. The ...
120 views

Solve seems broken after I installed the package Tomatlab.m

After I downloaded the Mathematica package ToMatlab.m, Solve does not work as before: ...
283 views

Using a Mathematica index as a DiscreteVariable in NDSolve when solving a coupled set of ordinary differential equations

Context Since the explanation below of the problem to be solved is lengthy, let me preamble this by saying that I have code that works to solve the problem, but I don't know whether (1) it's ...
69 views

Selecting the maximum value from the results returned by NSolve

I'm trying to select the maximum value from the answers Mathematica 7.0 is getting from a simple basic NSolve algebric equation : ...
321 views

Solve: Merging two branches of the solution

I have the following code: ...
60 views

using FindRoot to solve 3 simultaneous equations [closed]

I'm trying to solve 3 simultaneous equations derived from an electrical circuit of a common source amplifier. ...
159 views

How can I improve the solution of my PDE?

I want to improve the last code to find a better solution for umi. For now I'm using only MaxStepFraction. Also, when I put no ...
98 views

A question about calculus and Programming

I am a very new user and I would like to know how to calculate the following operations in Mathematica. Honestly this is not a homework. I am an french architect and I would like to be back in Math ...
81 views

Sign of a symbolic expression as a function of parameter values

I need to know the sign of the following expression for p[t] = z/(1-a), as a function of the parameters {a, b, c, z}: ...
142 views

159 views

A peculiar behavior of NSolve[]

NSolve[Power[x + 1, x + 1] - Power[x, x + 2] == 0, x, Reals] returns: {{x -> 3.14104}} Great. However, ...
I need to solve the following system of equations symbolically for a_i, b_i, and c_i: \...