Hi all

I dont know why some Z1 appears on the screen and the code does not converge.
please help me
thanks alooooot

restart;
n:=3;
nn:=3;
m:=1;
BB:=1;
BINF:=5:
pr:=7;
digits:=10;
>
eq1:=diff(f(tau),tau$3)+((3/5)*f(tau)*diff(f(tau),tau$2))-(1/5)*(diff(f(tau),tau$1))^2+((2/5)*tau*diff(h(tau),tau$1))-((2/5)*h(tau))-BB*diff(f(tau),tau$1)=0;
eq11:=(1/pr)*diff(h(tau),tau$3)+(3/5)*f(tau)*diff(h(tau),tau$2)=0;

h(tau):=sum(p^i*h[i](tau),i=0..nn);
f(tau):=sum(p^i*f[i](tau),i=0..n);

H1:= p*(diff(f(tau),tau$3)+((3/5)*f(tau)*diff(f(tau),tau$2))-(1/5)*(diff(f(tau),tau$1))^2+((2/5)*tau*diff(h(tau),tau$1))-((2/5)*h(tau))-BB*diff(f(tau),tau$1))+(1-p)*(diff(f(tau),tau$3)):
H11:= p*((1/pr)*diff(h(tau),tau$3)+(3/5)*f(tau)*diff(h(tau),tau$2))+(1-p)*(diff(h(tau),tau$3)):
>
eq2:=simplify(H1):
eq22:=simplify(H11):
eq3:=collect(expand(eq2),p):
eq33:=collect(expand(eq22),p):
eq4:=
convert(series(collect(expand(eq2), p), p, n+1), 'polynom');
eq44:=
convert(series(collect(expand(eq22), p), p, n+1), 'polynom');
for i to n do
s[i] := coeff(eq4, p^i) ;
print (i);
end do:
for i to nn do
ss[i] := coeff(eq44, p^i) ;
print (i);
end do:
s[0]:=diff(f[0](tau), tau$3);
ss[0]:=diff(h[0](tau), tau$3);
ics[0]:=f[0](0)=0, D(f[0])(0)=0, D(f[0])(BINF)=0;
icss[0]:=h[0](BINF)=0, D(h[0])(0)=1, D(h[0])(BINF)=0;

dsolve({s[0], ics[0]});
f[0](tau):= rhs(%);
#dsolve({ss[0], icss[0]});
h[0](tau):= -exp(-tau); #;rhs(%);

>
>
for i to n do
f[ii-1](tau):=convert(series(f[ii-1](tau), tau, nn+1), 'polynom');
h[ii-1](tau):=convert(series(h[ii-1](tau), tau, nn+1), 'polynom');
s[i]:=simplify((s[i]));
ics[i]:=f[i](0)=0, D(f[i])(0)=0, D(f[i])(BINF)=0;
dsolve({s[i], ics[i]});
f[i](tau):=rhs(%);
ss[i]:=(ss[i]);
icss[i]:=h[i](BINF)=0, D(h[i])(0)=0, D(h[i])(BINF)=0;
dsolve({ss[i], icss[i]});
h[i](tau):=rhs(%);

end do;

f(tau):=sum((f[j])(tau),j=0..n);
with(numapprox):

plot(diff(f(tau),tau),tau=0..5,color=blue,style=point,symbol=circle,symbolsize=7,labels=["tau","velocity"]);
plot(pade(diff(f(tau),tau), tau, [7, 7]),tau=0..5,color=blue,style=point,symbol=circle,symbolsize=7,labels=["tau","velocity"]);

x*(y+z)/x

convert any polynomial to Divide(Mult(x, Plus(y+z)), x)

Hi can you please help me? I want to write a program in Maple code, using the Newton-Raphson method, to solve the equation tan(x) −x-1=0 .  the approximate root is 1.5.
I tried doing this using a while loop to compare the last and current iterates, but something is not working.
so can you please help me do that?

Thanks

y = -x+sqrt(-5*x)

how to plot this in 2d or 3d graph

Hi,

What is the reason/Why: 

Error, (in dsolve/numeric/bvp) unable to achieve requested accuracy of 0.1e-5 with maximum 128 point mesh (was able to get 0.66e-1), consider increasing `maxmesh` or using larger `abserr`

Thanks for the help :)

I'm trying to plot the direction field of the second order differential equation x''=x'-cos(x) using dfieldplot: 

> with(DEtools); with(plots);
> f1 := (x, y) options operator, arrow; diff(x(t), t)-cos(x(t)) end proc;
/ d \
(x, y) -> |--- x(t)| - cos(x(t))
\ dt /
> dfieldplot([diff(x(t), t) = y(t), diff(y(t), t) = f1(x(t), y(t))], [x(t), y(t)], t = -2 .. 2, x = -2 .. 2, y = -2 .. 2);
Error, (in DEtools/dfieldplot) cannot produce plot, non-autonomous DE(s) require initial conditions.
>

The error I'm getting says I need initial conditions, but I wasn't provided with any. Is there another way to plot this? Sorry if this is dumb question, but I've only ever plotted first order equations.

The equation

x^7+14*x^4+35*x^3+14*x^2+7*x+88 = 0

has the unique real root

x = (1+sqrt(2))^(1/7)+(1-sqrt(2))^(1/7)-(3+2*sqrt(2))^(1/7)-(3-2*sqrt(2))^(1/7).

Here is its verification:

Is it possible to find that in Maple? I unsuccessfully tried the solve command with the explicit option.

I was required to purchase Maple 17 for my upcoming Calculus III course, and until now, I have been using my TI-Nspire CAS CX for all of my CAS needs.  I am going through various tutorials/labs in an effort to learn how to use the Maple 17 Software. As a part of this process, I am attempting to solve a system of equations and was told to use the following command:

>solve({2*x+3*y=7,5*x+8*y=9},{x,y}); 

in order to receive the answer 

{y=-17,x=29}.

Instead, I have received the following error message, which has no help attached to it through the help page.

solve({2*x+3*y = 7, 5*x+8*y = 9}, {x, y});
Warning, solving for expressions other than names or functions is not recommended.

I am hoping this has something to do with Mac vs. Windows software, and that it has a simple solution.  I would greatly appreciate any guidance!

There are two normals to a point on a curve.  How do I get the PlotPositionVector of Student[VectorCalculus] to point in the other direction. 

with(Student[VectorCalculus]:

R1:=PositionVector([p,p^2],polar[r,t]):

PlotPositionVector(-R1,p=1..2,normal=true,points=[1.5])

The normal vector points towards the insided of the curve.  Can I use PlotPositionVector to have it point the opposite way (towards the outside of the curve)?

restart:

ODE:=diff((-diff(u(y),y))^n,y)=A;

bcs:=D(u)(0)=0,u(h)=0;

dsolve({ODE,bcs});

             u(y) = 0

Does anyone has any maple worksheet that generate surface using the PDE method described in this article?  I am trying to learn this method but I am not familiar with the mathematics to do it although the paper gives some description of it.  I hope someone can demonstrate the procedure in Maple.  Thanks

http://www.researchgate.net/publication/259095177_Automatic_shape_optimisation_of_pharmaceutical_tablets_using_Partial_Differential_Equations/file/72e7e52a87ed129d4a.pdf

Pleas i want to do continued fractional expansion to transfer function G(s) with numerator and denomenator as a polynomial in Lplace operator s.

with my gratitude

I need to maximize two multivariate objective functions (f(x1,y1,z1,t1) and g(x2,y2,z2,t2)) with inequality and nonnegativity constraints (x1, x2>0 and y1, z1, t1, y2, z2, t2 >=0). I am looking for parametric not numerical solutions.

What is the best way to find the solution to such a problem using maple?

Hi:

i will plot the following equation so that the horizontal axis in terms of omega and vertical axis in terms of a,but i can not do it,can i help me?

equation:

Hi ,

I would like to resolve the Kortweg and de Devries equation :

> KDV2:= diff( u(X,T), T)+ 6*u(X,T)*diff(u(X,T),X)+ diff(u(X,T),X$3);

I used pdsolve but I have a problem to enter the IBC :

I want

u(infinity, t) =0
u( -infinity, t )=0

u ( x, 0 ) = 1

So I did :

> SOL:=pdsolve(diff( u(X,T), T)+ 6*u(X,T)*diff(u(X,T),X)+ diff(u(X,T),X$3)=0,{u(-10, T) = 0, u(10, T) = 0, u(X, 0) =1},numeric,time=T,range=-10..10);

But it doesn't work.

( I remplace infinity by 10 because then I want the graphic representation of the solution )

Could you help me please ?