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I have the following function

where A,B,Ψ, K1,K2,K3,α,β are all constants.

How to find the value of m for which the above expression is 0 or approximate to 0 for different values fo the constants.

e.g., Fixing all the parameters except A, I want to find the values of m for different values of A. How to do that in maple?


hi every one..

how i solve numerically  couple equations which attached below .in solve this equation we must  starting from a very small value of V(voltage) with initial guesses for x1 and x3

near zero and using find root is noted that  the solution at this voltage step are used as initial guesses

for the next voltage step, and the process is repeated..



Today I've playied a bit with CellDecomposition from the RootFinding package and for one of the systems with which I've playied I got an error which seems to me to be a bug related.

In particular, 


m := CellDecomposition([x^3-y^2 = 0, x^2+y^2-1 < 0], [x, y])

Error, (in RootFinding:-Parametric:-CellDecomposition) Segmentation Violation occurred in external routine


Did I make a mistake somewhere or Maple 2015.1 faild?

If there is  an equation or are several equations, I need to obtain all the roots, how can I do???


fsolve ? rootfindings? or what?


If an examples of actual is given,  That will be perfect  !!!



Hi All,

I want to solve for G, but cant seem to figure it out. Can anyone tell me what am I missing or doing wrong?


SSD:= ((155/9)*2.5)+((155/9)^2/(2*9.807*0.346));
Lc:= 2*SSD-(2*(sqrt(1.08)+sqrt(0.6))^2)/(G+0.04);
Ls:= 2*SSD-(2*(0.6+SSD*tan(Pi/180)))/(G);
Lcon:= 202-Lc-Ls;
Eq:= (G-0.043)(Lc/2)+(-G)(Ls/2)+G*Lcon-0.043*Lc=14;



thank you

The issue I am currently having is that, while analyticity (and physics) indicates a certain function must have roots, fsolve is having trouble finding them. In fact, I have even found roots manually in a certain region myself, simply inputting into the function various values until I found them. However, fsolve does not seem to want to find these roots, and I believe it is a numerics issue: when I changed the digits around, for extremely low values of Digits, it would find a root (even though it was incorrect). Further, this problem arose elsewhere in the domain of interest for other values of Digits (in particular, for Digits:=5, fsolve failed in a region it had not failed before).

The region of interest is the "peak" of the output of poleR(M0, 0.935, mK), which should be somewhere around M0 = 0.95 or so. However, because fsolve cannot find the roots, the plot cannot be made.

Anyone have any ideas as to why fsolve cannot find the roots? I was also experiencing issues with some of these functions having multiple roots, which itself is weird as well (note that I am working over the complex plane).

Attached is the document.

Any ideas?

The algorithm that I need to replicate is as follows:

real function f(x,y)

integer n; real a,b,c,x,y



for n=1 to 3 do





end for

end function f

How can I define f,a as  functions that I am later using as variables(in f=f+2cf,b=(a/f)^2)? also, is n just a variable for iteration? 


I've got a function f(x_n) = (x_n-1)^3

and need to show that for the iterative method

x_(n+1)= x_n - f(x_n)/(sqrt(f'(x_n)^2-f(x_n)*f''(x_n), at a simple root we have cubic convergence while at a multiple root, it converges linearly.

I understand that the approach is to write either a recursive function or a sequence, but i'm confused about the structure since both x and n are being incremented


I have a rather complex expression that I want to find the zero for as a function of two other parameters, i.e. I have a function

Denom := (s,M,g) -> stuff

that I want to find the zero of for a variety of values of M and g. In some cases the solution will be complex, which is entirely acceptable. However, the real part of the solution should never be negative, and yet that is the kind of result I am getting.

As an example (illustrated in the worksheet, when attempting to find the zero for M = 3 and g = 0.2, fsolve gives me s = -6.1 -1.4i. However, when I plot the function with the parameters input already, I can clearly see a zero at s = 9 with no imaginary component. Why won't fsolve find this zero? How can I make it do so?

See the bottom of the attached worksheet for the main problem.

Hi, I am using Maple 18 and struggling with plotting Newton's Method.

I am wanting use the function f(x)=x^3 +cx + 1 where c is a parameter and uses 100 parameter values between -2 and 0, with 100 iterations of each parameter.

Any help would be brilliant.

Thanks in advance,


I am numerically solving a nonlinear system of nine equations. How long can I expect it to take?

I have run it for 30 minutes and it has not solved yet.

Here is the system of equations:









0 = N - S - T - H - C - C1 - C2 - CT1 - CT2;

and I have numeric values for Lambda, beta, tau, mu, mu_T, mu_A, rho_1, rho_2, psi, gamma. The only parameters left are eta_1, eta_2.

Thank you.

Let's say I have 2 functions, the first being y=sin^2(x) and the second one is y=e^(-x)cos(x). When I try to solve on Maple, it only gives me one intersecting point, while I would like to see ALL intersections between the 2 functions. How would I go about doing this?

To motivate some ideas in my research, I've been looking at the expected number of real roots of random polynomials (and their derivatives).  In doing so I have noticed an issue/bug with fsolve and RootFinding[Isolate].  One of the polynomials I came upon was

f(x) = -32829/50000-(9277/50000)*x-(37251/20000)*x^2-(6101/6250)*x^3-(47777/20000)*x^4+(291213/50000)*x^5.

We know that f(x) has at least 1 real root and, in fact, graphing shows that f(x) has exactly 1 real root (~1.018).  However, fsolve(f) and Isolate(f) both return no real roots.  On the other hand, Isolate(f,method=RC) correctly returns the root near 1.018.  I know that fsolve's details page says "It may not return all roots for exceptionally ill-conditioned polynomials", though this system does not seem especially ill-conditioned.  Moreover, Isolate's help page says confidently "All significant digits returned by the program are correct, and unlike purely numerical methods no roots are ever lost, although repeated roots are discarded" which is clearly not the case here.  It also seems interesting that the RealSolving package used by Isolate(f,method=RS) (default method) misses the root while the RegularChains package used by Isolate(f,method=RC) correctly finds the root.

 All-in-all, I am not sure what to make of this.  Is this an issue which has been fixed in more recent incarnations of fsolve or Isolate?  Is this a persistent problem?  Is there a theoretical reason why the root is being missed, particularly for Isolate?

Any help or insight would be greatly appreciated.


I am trying to write a single procedure to find the root of any function using the Newton-Raphson method, given the initial approximation and the tolerance. If this fails to converge, the program must then use the Bisection method to find the root. Need some help please. The current procedure i have done is only coming out with the first Iteration 

Thanks for the help!

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