Items tagged with rootof

Is it possible get a solution of this equation without RoofOf in form explicit?

Hi!

I have a question here. Is there any way to simplify a complicated number expressed in terms of RootOf() forms?

I got numbers like

c:=(3/128)*RootOf(3*_Z^4-20*_Z^3+50*_Z^2-20*_Z+3)^3-(5/32)*RootOf(3*_Z^4-20*_Z^3+50*_Z^2-20*_Z+3)^2+(1/64)*sqrt(4+6*sqrt(6))+(25/64)*RootOf(3*_Z^4-20*_Z^3+50*_Z^2-20*_Z+3)-(3/128)*RootOf(3+3*_Z^2+(-3*RootOf(3*_Z^4-20*_Z^3+50*_Z^2-20*_Z+3)^3+20*RootOf(3*_Z^4-20*_Z^3+50*_Z^2-20*_Z+3)^2-47*RootOf(3*_Z^4-20*_Z^3+50*_Z^2-20*_Z+3))*_Z)-5/64

I am quite sure this number is 0: 
evalf(c, 100) gives:
0.+1.*10^(-101)*I

However, I tried simplify(c) and convert( c, 'radical' ) and some other choices of simplify() function. None of them can output 0. Is there any maple functions that can help me to simplify this kind of expressions?

Thanks!

William

While exploring a relatively simple sin equation, depending on how I process I get different forms of the root. Numerically, they appear to be the same, but I am having difficult figuring out how they could be, and would appreciate some guidance.

The more standard root is

21*arccos(RootOf(448*_Z^7+192*_Z^6-784*_Z^5-288*_Z^4+392*_Z^3+108*_Z^2-49*_Z-6, index = 2))/Pi


The less standard approach is

-(21*I)*ln(RootOf(7*_Z^14+6*_Z^13+6*_Z+7, index = 2))/Pi

Both of the RootOf appear to be irreducible, and it is not clear to me how you could transform the more complicated degree 7 polynomial into the simpler degree 14 polynomial while still retaining exactly the same roots?

If the equivalence holds up then it would be much easier for me to generalize the second form than the first.

I was, by the way, looking at minimizing sin(2/7*Pi*x) _+ sin(1/3*Pi*x) over its first complete cycle, as part of working up to a general rule for minimizing sum of sin of different amplitude and periods. diff(), then standard form is solve(), and less standard form is solve() of convert/exp() of the diff()

 

I wish to solve for k interms of x, e is a constant in the equation k=x+e*sin(k). Using the solve function, i got 

RootOf(_Z-x-e*sin(_Z)) and using the function allvalues(RootOf(_Z-x-e*sin(_Z))) still gave the same expression in _Z. Please is there a way out because I need the value of  as a substitute to another equation. Any help will be highly appreciated.
 

 Hi all,

 Is there anyone who could help me with this error? I am sure there is at least one solution for the equation.

 Thanks

Maple Worksheet - Error

Failed to load the worksheet /maplenet/convert/EQ.mw .

Download EQ.mw

suppose one has a solution to a system of equations that returns results as RootOf(X) expressions. I would like to know if there is a procedure for extracting the "X" from the RootOf for the purpose of further algebraic analysis.

hello.

i have two problem in maple file, that is attached..

one of them is RootOf...note that i suppose that [varepsilon := -2.3650203724313] for i can going on following calculation

and second is  Float(undefined) in calculation integral

please help me

thanks

(m=1_n=6)2.mw

Here is my code in Maple.

 

#Solve the initial-value problem using the technique of question 2. Find the implicit solution.
eqn3:=(exp(x)+y)*dx+(2+x+y*exp(y))*dy=0;
(exp(x) + y) dx + (2 + x + y exp(y)) dy = 0
#subject to y(0)=1.
M:=exp(x)+y; N:=2+x+y*exp(y);
exp(x) + y
2 + x + y exp(y)
int(M, x); int(N,y);
exp(x) + y x
y x + 2 y + y exp(y) - exp(y)
implicitsoln1 := exp(x)+y*x+2*y+y*exp(y)-exp(y)=C;
exp(x) + y x + 2 y + y exp(y) - exp(y) = C
y1 := solve(implicitsoln1,y);
RootOf(-exp(_Z) _Z - _Z x + C + exp(_Z) - 2 _Z - exp(x))
C:=subs({x=0,y=1},lhs(implicitsoln1));
exp(0) + 2
y1;

 

How do I get it to to not have "root of" and give me a more specific solution.

Does `evala/toprof` still exist in newer Maple versions, or is there an equivalent?

 

With the following equation

eqn:=y=1/2+(1/2)*erf((1/2)*sqrt(2)*(x-mu)/sigma)-exp(-lambda*(x-mu)+(1/2)*lambda^2*sigma^2+ln(1/2-(1/2)*erf((1/2)*sqrt(2)*(lambda^2*sigma^2-lambda*(x-mu))/(lambda*sigma))));

and with

x:=solve(eqn,x) assuming sigma > 0, lambda > 0;

I got the following solution

x := -(1/2)*(-lambda^2*sigma^2-2*lambda*mu+2*RootOf(-exp(_Z)*erf((1/4)*sqrt(2)*(lambda^2*sigma^2+2*_Z)/(lambda*sigma))+exp(_Z)+erf((1/4)*sqrt(2)*(-lambda^2*sigma^2+2*_Z)/(lambda*sigma))+2*y-1))/lambda;

In order to get rid of RootOf I gave the command:

allvalues(%);

However, RootOf did not disappear. How should I proceed? 

 

hi...how i can gain result for solve three equations,in which term '' Root of'' dont appear?

thanks

root.mw

restart; Q1 := aa*(y-x)

aa*(y-x)

(1)

Q2 := -ll*x*z+bb*x

-ll*x*z+bb*x

(2)

 

-ll*x*z+bb*x

(3)

Q3 := -cc*z+hh*x*x+kk*y*y

hh*x^2+kk*y^2-cc*z

(4)

SOLL := solve({Q1, Q2, Q3}, {x, y, z})

{x = 0, y = 0, z = 0}, {x = RootOf((hh*ll+kk*ll)*_Z^2-bb*cc), y = RootOf((hh*ll+kk*ll)*_Z^2-bb*cc), z = bb/ll}

(5)

``

 

Download root.mw

Dear all,

I am trying to solve the following system of equations by using dsolve, but I get the error:  error, (in RootOf) expression independent of, _Z, could you please help me to solve it. Thank you.

restart;
Digits := 20;
with(plots);
Nr := .1; Nb := .3; Nt := .1; Rb := 0; Lb := 1; Le := 10; Pe := 1; ss := .2; aa := .1; bb := .2; cc := .3; nn := 1.5;
Eq1 := nn.(diff(f(eta), eta))^(nn-1).(diff(f(eta), `$`(eta, 2)))-(nn+1)/(2.*nn+1).eta.(diff(theta(eta), eta)-Nr.(diff(h(eta), eta))-Rb.(diff(g(eta), eta))) = 0;
Eq2 := diff(theta(eta), `$`(eta, 2))+nn/(2.*nn+1).f(eta).(diff(theta(eta), eta))+Nb.(diff(theta(eta), eta)).(diff(h(eta), eta))+Nt.((diff(theta(eta), eta))^2) = 0;
Eq3 := diff(h(eta), `$`(eta, 2))+nn/(2.*nn+1).Le.f(eta).(diff(h(eta), eta))+Nt/Nb.(diff(theta(eta), `$`(eta, 2))) = 0;
Eq4 := diff(g(eta), `$`(eta, 2))+nn/(2.*nn+1).Lb.f(eta).(diff(g(eta), eta))-Pe.((diff(g(eta), eta)).(diff(h(eta), eta))+(diff(h(eta), `$`(eta, 2))).g(eta)) = 0;
etainf := 10;
bcs := f(0) = ss/Le.(D(h))(0), theta(0) = lambda+aa.(D(theta))(0), h(0) = lambda+bb.(D(h))(0), g(0) = lambda+cc.(D(g))(0), (D(f))(etainf) = 0, theta(etainf) = 0, h(etainf) = 0, g(etainf) = 0;
dsys := {Eq1, Eq2, Eq3, Eq4, bcs};
dsol := dsolve(dsys, numeric, continuation = lambda, output = procedurelist);
Error, (in RootOf) expression independent of, _Z

Hi,

I have been trying to solve the following equation with respect to y, but I have not been successful. In fact, I always get answer RootOf(...). I should mention that all variables and parameters are real non-negative. I have also tested with "assume", but it did not help. Any suggestion would be appreciated. 

with(RealDomain):

eq := -((y-b)*mu-y)*x^beta*alpha+y^beta*varepsilon*(x-a) = 0

-((y-b)*mu-y)*x^beta*alpha+y^beta*varepsilon*(x-a) = 0

(1)

solve(eq, y)

RootOf(-x^beta*alpha*b*mu+x^beta*alpha*mu*_Z-x^beta*alpha*_Z+_Z^beta*varepsilon*a-_Z^beta*varepsilon*x)

(2)

remove_RootOf(%)

-x^beta*alpha*b*mu = 0

(3)

``

``

Download Equation.mw

 

Thanks.

hi.please see attached file below and help me for gain real or complex answer 

with out show answer in root of manner

thanksroot_of....mw

Hello everyone! I got some trouble in process a list. Hope you can help:

Assume i got a list like this:

 

{{k = k, l = RootOf(_Z^2+_Z*k+k^2-1), o = -k-RootOf(_Z^2+_Z*k+k^2-1)}, {k = k, l = RootOf(_Z^2+_Z*k+k^2+1), o = -k-RootOf(_Z^2+_Z*k+k^2+1)}, {k = 0, l = 1, o = -1}, {k = 0, l = -1, o = 1}, {k = 1, l = 0, o = -1}, {k = 1, l = -1, o = 0}, {k = -1, l = 0, o = 1}, {k = -1, l = 1, o = 0}, {k = RootOf(_Z^2+1), l = 0, o = -RootOf(_Z^2+1)}, {k = RootOf(_Z^2+1), l = -RootOf(_Z^2+1), o = 0}}

 

Now all i want is remove Complex and RootOf from this list, how can i do that?

Thank for your reading adn your help!

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