12 questions linked to/from First positive root
1 vote
168 views

### Finding Maximum Root [duplicate]

How can I find the greatest root for a polynomial if the polynomial degree is very large. One way is using NSolve. This command can find all roots in numeric. Then, ...
• 739
4k views

### Can mathematica solve this equation?

I have the following Mathematica code to solve an equation coming from isoparameteric finite element for quadratic tetrahedron element. I need to get the iteroplation fast and accurate. I only find ...
• 511
12k views

### Forcing FindRoot to return only real solutions

FindRoot documentation reports that if the equation and the initial point are reals, the solutions are searched in the real domain. However, in the following case I ...
2k views

### How to obtain numerical solutions of a two-variable equation?

I have a two-variable function: f[x_, y_] := (4 y^2 - 6) (Cos[y π] Cos[x] - Cos[2 y π] Sin[x]) How can I find all the numerical solutions for $x$ and $y$ such ...
243 views

### Numerical solution of the inverse contour plot

I have a function $f(u,v)$ on some domain of $(u,v)$ and would like to find (numerically) the set of couples* $(u_0,v_0)$ s.t. $f(u_0,v_0)=0$, for instance (just and example to illustrate, in practice ...
540 views

### Finding Real Roots and Determining Range

I am interested in determining the minimum and maximum values of the real roots of polynomials of form $P(x)=\sum_{k=0}^n a_{k} x^k$ where $n$ will have a defined value (say 3,4,5...) and $a_k$ are ...
• 189
3k views

### FindRoot in range

I am trying to find all roots in a range, using y /. FindRoot[Sin[y] == 0, {y, #}] & /@ Range[7] which gives ...
• 8,678
2k views

### Multiple ranges in one plot [duplicate]

Possible Duplicate: 1 Plot, 2 Scale/Axis Generating a broken or snipped axis in ListPlot I have data in several ranges which I, when I plot together, is not very useful. I was thinking about ...
• 251
367 views

### how to find numerical zeros of $f(z)$ in a compact complex domain [duplicate]

I encountered a function $f(z)$ with several zeros in a region $1<\Re(z)<2, 3<\Im(z)<4$. These zeros are visible in a three dimensional plot like ...
• 303
1 vote
470 views

### Fastest way to find roots

I'm working with generative polynomials, and would like to know if there is a faster way to calculate roots. Using the technique below I've managed to cut the time down significantly. However at n=35, ...
• 115
719 views

### How can I obtain the complex root of an equation with FindRoot

I want to obtain the complex roots of some equations that are similar,but each of them has a different condition. this difference is the value of α in these ...
63 views

### Selecting results according to the constraint [duplicate]

It is very likely that this question is a duplicate, but unfortunately I have not found the solution. Among the results of a Solve, I would like to apply for the ...
• 9,233