## math...

Write the equation given to ordered pairs. 1. (1,2) and (9,6) y = 2. (5,2) and (3,4) y = 3. (-5,-5) and (5,4) y = 4. (4,6) and (5,4) y = 5. (-2,0) and (3,5) can sum 1 please help her im having trouble!!!!!!! thnx SOoo much =)

## Simple Totalizer for dynamic simulation question...

Hello again,

I have another simple question. I have a dynamic simulation that I've put together, and I'm solving the system of equations using "dsolve(odeset,numeric)", and all is going well there. However, I added a "product totalizer" that integrates my exit flow with the command:

Ptotal := ptot(t) = int(Fexit, t)

And that works well if the Fexit is a fixed number in my simulation. However, I wanted to change the Fexit variable at certain points in time, so I used the piecewise command:

Fexit := piecewise(`and`(t >= 25, t < 30), 2, `and`(t >= 35, t < 34), 2, 0)

The simulation looks fine with the piecewise logic, but the integration above does not. It looks like the integration resets itself to zero where the steps occur. So my questions are:

## How to plot this output?...

I would like to represent the frequency of the output (values of x, values of y) of the following commands.. restart: with(stats): with(Optimization):stats[random, normald](1); for i from 1 to 10 do z:= Maximize(1/3*ln(x)+1/3*ln(y), {x+y

## Odd output when solving ODE set, "table"...

Hello, I was curious if someone could enlighten my on what's going on here. I put together a set of ODE's and solved them. I then went back and changed some of the parameters, but not the form, of the ODE's. The output of my ODE set now has a "table" comment in it, and I don't know why. For example, one of my initial ODE's is: XMB; (diff(V(t), t))*X(t)+V(t)*(diff(X(t), t)) = .3*S(t)*X(t)*V(t)/(.1+S(t)) after I change some of my parameters, I get this as output: XMB; (diff(V(t), t))*(table([inlet = 0]))(t)+V(t)*(diff((table([inlet = 0]))(t), t)) = -0.1e-1*(table([inlet = 0]))(t)+.3*(table([inlet = 1.0]))(t)*(table([inlet = 0]))(t)*V(t)/(.1+(table([inlet = 1.0]))(t))

## Debugging Maple code...

What tools are available to help with the search for syntax errors within Maple code? It seems to me the built-in debugger is designed to assist with the testing of Maple code with no syntax errors. While this is important, and useful, the code has to be syntactically correct before this is of any use. Here's the situation I am facing. I have a file with more than 3500 lines of Maple code. Close to 1000 lines is the definition of a maplet, which has to be in one execution group. If there is a single missing comma, square bracket, or parenthesis, Maple will generate an error message and will place the cursor somewhere within the offending execution group. I have seen enough error messages that I know what they mean; I'm not complaining about the error message. My complaint is about the location of the cursor. While the location is deterministic, it is rarely close to the actual location of the error. Does anyone have any useful tips for how to locate the source of syntax errors within large Maple programs?

## How do I numerically solve differential equations?...

None of the built-in features of Maple will help me numerically solve the kinds of complicated differential equations I want. I was hoping that Maple's option in dsolve of solving by Taylor series would at least grind out the first nine terms of the Taylor series expansion of the solution y(x) of e.g. x^3 + (y'(x) - 9*x)^(5/(y(x)+2)) + 4*(x-y(x))^(y'(6*x+4)) = 0 subject to y(1)=0. I dumped in functional equations, too, to see if Maple could handle it. Ok. So, for something like this, R(x,y(x),y'(x),y'(6x+4))=0 Maple should be at least able to do the first 9 differentiations to express

## how do i get both real part and imaginary part fro...

My expression is exp(mu*t), and 'mu' is a complex number.

## Maximization of a function over a given range...

I am having difficulty getting Maple to find the optimal solution over a specified range. That is, I want to limit the possible range of my maximizers. For my problem I am maximizing the expression "payoff" with respect to p and s and want to tell Maple to search for all solutions where s<pa.

I have the following expression for variable x

x:=-1/4*(s^2-pa^2+4*pa-4*s-4*p)/(s-pa);

where x is an input to the function payoff that I wish to maximize:

payoff:=p*x + s*subs(Q=x,y) + m*(1-subs(Q=x,y)));

and

y:=int((d-s/2),d=s/2..Q+s/2)+int(Q,d=Q+s/2..1));

Now, defining the FOC of payoff as

## solve for infinity...

A colleague just asked me what Maple would do if asked to solve an equation in which the right hand side is infinity. I didn't really know what it would do, so we did some tests:
```f := (x-1)/expand((x-1)*(x+1)*(x-2)):
solve( f=infinity, x );
1, -1
solve( 1/f=0, x );
2, -1
solve( denom(f)=0, x );
1, 2, -1
```
I could not explain the response to the first solve command. Can you? Thanks in advance, Doug

Anyone help me with thes practice problems i've done like 25 others. I am not sure if iam simply brain fried at this point or if i truly don't understand. Any help is appreciated thanks, florida nurse #1) Solve x(2x+3)= -4 possible answers are as follows a) [-5 +-i(sqrt23)/3] b)[-2 +-i(sqrt21)]/4 c)[-3 +-i(sqrt23)]/4 d)[+4 +-i(sqrt23)]/5 #2) Find the polar equation for the graph of a circle which is centered at the origin of a graph (0,0) and the equation of the graph is x^2 +y^2= 4. any and all help is much appreciated.

## Customized Units...

Hello, I am very new to using Maple, so I must apologize for my ignorance in advance. I basically have 2 questions, 1) How do I force the use of a preferred unit that may not be the default for a particular unit system. For example, I prefer cm for length and keV for energy. I would like these to always be assumed by Maple. also 2) How can I use a unit that does not appear to be part of any unit system, such as "neutrons". I would like to enter values such as 1E8 [neutrons/cm^2] . . . etc. How does one do this in Maple. I appreciate your input. Best regards, GL Columbi

## How to make the "plot" command work?...

In maple 11 I have defined: f := x -> e^(-x)*sin(x); then I have tried to get maple to draw the above mentioned: plot(f(x),x=0..2*Pi); What happens is that I see a the coordinat-system but with no drawings in it. Can anybody help me? Regards Simon