I am trying to produce a 2-D plot of the function (sin(x))^2 using the context menu in document mode but Maple returns this error:
sin(x)^2 -> Error, invalid input: smartplot uses a 1st argument, f (of type {algebraic, algebraic = algebraic, {set({algebraic, algebraic = algebraic}), list({algebraic, algebraic = algebraic})}}), which is missing
It does the same when I change the function. What's wrong?
Thanks
Stéphane

All:
I am trying to find the critical points for f(x):=((x-1)^2)^(1/3)-.5*x^2 over [-2, 2]
It has two stationary points
solve(diff(((x-1)^2)^(1/3)-.5*x^2,x)=0,x);
-.5732093133, 1.180229770
and one singular point.
1
But CriticalPoints(((x-1)^2)^(1/3)-.5*x^2, x); only finds
-.5732093133, 1
Can anyone explain why?
Thanks

Question 1
Forty acres of land were sold for $81000. Some was sold at $2400 per acre and the rest at $1800 per acre. How much was sold at each price.
Question 2
An apartment owner rents one-bedroom apartment for R 525 and two bedroom apartments for R600. A total of 13 apartments rent for R7500 a month. How many of each type does she have?

Hi all,
Here are my questions:
1) How do i perform small-angle approximation (linearization) on a nonlinear DE using Maple. This is necessary to create a state-space representation of the DEs. By small-angle approximation i mean that:
sin(theta(t))=theta(t)
cos(theta(t))=1
theta(t)^2 = 0
theta(t)*alpha(t)=0
and so on....
I tried using manual substitution using the "subs" command. It is not a very feasible method. I have tried "dsolve" command. Not what i want since i only want to linearize the DEs and not solve for a particular angle.
2) My second question is regarding defining outputs of the "DiffEquation" command. Usually it will go:

Hi -- I am trying to plot a (fairly basic) procedure, Q_plot, which defines a piecewise function (three pieces).
Q_plot evaluates no problem at the command prompt for all three regions -- but only plots for two of the three regions. Resulting in a big hole in the middle of my graph!
Hmm?
I've uploaded a copy of the worksheet, with the plot (and the aformentioned hole in the middle). Thanks
Here's the link to the worksheet:
http://www.mapleprimes.com/files/5475_Diagnostic-proc-Q.mw

Hello all,
I have a function, a(r,zeta). For a particular range of values of zeta and r, I'd like to find out which value of zeta will give me the smallest maximum point on the function. I've used the Optimization:-Maximum function to give me the maximum point at a specific value of zeta, but after that I was changing zeta using trial an error to find the smallest maximum, and was wondering if I could get Maple to compute that for me.
Thanks
--Amr

When using Latex for MapleTA questions, one can use the command switch in order to change the name of the variable.
The question now is: How to use this command or a different one to change a function to another one? For example, if one wants to ask the value of
\sin($z(x))
where z is not always the same function, say
z=Switch(rint(2), \arcsin(x), \arcos(x)),
how can we make this work?
An answer would be extremely helpful!!

Hello everyone!
My question is a stated above...
I am trying to find a solution to the wave equation for a standing wave in a rope, with damping.
my trial function is : exp(-I*(omega*t+k*x)) * exp(-tau*x)
I am still working on my expression for tau, but besides that I have no idea how to plot this.
I started to plot exp(-I*(omega*t+k*x)) with omega = 2 and k = 4.
I simply can't figure it out, its probebly because it is complex....
Somebody experience with this?
already thanks.

Hello!

I have a system of ODEs which I can solve numericaly with Maple. What I try to do (still without success) is to compute the i-th derivatives of the solutions at a certain point of the interval. For example (a mini-version):

eq_0 := D(x[0])(t)=(-2*x[0](t))/(1-x[1](t));

eq_1 := D(x[1])(t)=(2*x[0](t))/(1-x[1](t));

sys := {eq_0, eq_1, x[0](0)=1, x[1](0)=0};

fcns := {x[0](t), x[1](t)};

p:=dsolve( sys, fcns, numeric, method=classical[rk2], output=listprocedure );

(OK, this is very easy, but it is only an example.)

Now I want to compute the 6-th derivative of x[0](t) at t=1/2. The analytic form can be obtained if D(x[0]) is differentiated 5 times and x[0] and x[1] are substituted by their numerical solution. I have read about differantiating in Maple, but I still cannot get this work.

Hi -- I want to check the sign of a polynomial. Here's the polynomial expression
(1/16)*(9*s^5-3*s^4*m-34*s^4*pa+12*s^3*m*pa+46*s^3*pa^2-18*s^2*m*pa^2-24*s^2*pa^3
+12*s*m*pa^3+s*pa^4-3*m*pa^4+2*pa^5-16*s^4+64*s^3*pa
-96*s^2*pa^2+64*s*pa^3-16*pa^4+16*p^2*s+48*p^2*m-64*p^2*pa)/(s-pa)^4
and here's the parameterization: pa>s and pa>m.
Generally checking the sign of the polynomial involves checking the signs of the factors...so, I'd like to factor the above expression. I haven't worked with "factor" much in Maple. Applying it as just factor(expr) with expr equal to the above expression does nothing. So not sure the best approach.

Hello again Maple experts,
I have four nonstochastic variables s11, s12,s21,s22.. from there I have 2 random variables X1 and X2 (to begin, it may be a uniform distribution U[-1,1]) . I generate the random variables y1 and y2:
y1 = min(s11+X1, s21+X2)
y2 = min(s12+X1, s22+X2)
1. How could I obtain with MAPLE the distribution of
Z= (y1)^(1/2)+log((40-y2)*(80+2*y2-3y1))?
2. And how could I obtain the expected value of Z?
Thanks in advance for any help.
Regards,
Jean

I have a nested list, say
test:=[[1,2,3,4],[5,6],[7,8,9]]:
and I want to use something like
map(x->1/x,test);
to get
[[1, 1/2, 1/3, 1/4], [1/5, 1/6], [1/7, 1/8, 1/9]]
but it won't work...
map doesn't go in nested lists and it rather returns
[1/[1, 2, 3, 4], 1/[5, 6], 1/[7, 8, 9]]
I can't find an example about this simple problem,
I'm sure it must be easy though but I'm losing my mind on this one.

Hi, I have been trying to use Euler's method to calculate approximate values on maple 11, and I cannot get it to work. Can someone show me the exact things to enter? I am given y', an initial value, and step size. I looked it up online and followed various directions, but still haven't been able to get an answer.

Assuming that I have the following
row1 = a, b, c
row2 = a, b, c
row3 = b, c , a
I would like to obtain for each column the frequencies:
column1 a: 2, b: 1, c:0
column2 a:0, b:2, c: 1
column3 a:1, b:0, c:2
How could I do it with maple?
Do I need to use some package?
Thanks in advance,
Jean

Hi,
I am trying to evaluate a number of N[i,j] variables and part of the process of finding them includes "Int" and afterwards "evalf". In case I calculate them manually as in (functions, variables and constants previously defined):
G11 := diff(psi2, a[1], a[1]);
dpsi2 := diff(psir2, a[1], a[1])+diff(psiz2, a[1], a[1]);
Izr := -E*(Int(u*G11, [z = -infinity .. infinity, r = 0 .. infinity]))+Int(u*((j*g0+j^2/r^2+(1/4)*g0^2*r^2-2/rho)*G11+dpsi2), [z = -infinity .. infinity, r = 0 .. infinity]):
Izr2 := evalf(Izr);
N[1,1] := (a[1]*a[1])*Izr2;
I obtain neat results for Izr2 and N[1,1] (i.e. the integration is done and results in a number).