## Can't maple even maximize such a simple function?...

Tried to maximize a simple function f(t), failed. Converted it to different forms, still failed. Simplified the function a bit by hand and tried again, still fail. Only after some major simplification by hand and a transformation: u=s^2=(1/2-t)^2, it finally worked. I must be missing something. I thought such a simple problem should certainly be solved by maple in a flash. Can someone enlighten me please? Thanks a lot. > maximize(t^2*(1-t)^2*(1+t^2)*(1+(1-t)^2), t = 0 .. 1); / 2 2 / 2\ / 2\ \ maximize\t (1 - t) \1 + t / \1 + (1 - t) /, t = 0 .. 1/

## Converting fractures to regular numbers...

Question is easy but not for me :). How do I convert fractures into regular numbers. Thank you! Greetz Pieter

## Spider & fly Dudeney problem - a new twist...

Hi Please see Spiderflygrid2.mws A spider is on the floor of a cubical room of side 1. Its position is given. Where must the fly position itself to be as far as possible from the spider? My attempt minimizes the square of the twelve possible distances. This is m. m:=min(seq(cd[i], i=1..12)); Partial derivatives of m are found with respect to xf (the x coord of the fly) eq1:=diff(m,xf); ... & with respect to yf (the y coord of the fly) eq2:=diff(m,yf); These two equations are then solved simultaneously. solve({eq1,eq2}); Maple gives an error message - is this due to the discontinuities in the expression m? Or (more likely) a fault in my Maple code?

## operation on a function of time...

Hello - this is a novice's question: Consider the following: > E1 := a = b > E2 := b = c > eliminate({E1, E2}, {b}) [{b = c}, {a - c}] So this works. > E3 := a1(t) = b1(t) > E4 := b1(t) = c1(t) > eliminate({E3, E4}, {b1}) Error, (in eliminate/recursive) invalid subscript selector What should I do in the second set above to eliminate b1(t) and get the result a1(t) = c1(t)? Thanks.

## pdsolve with point-by-point initial condition...

I'm numerically solving, using pdsolve on Maple 9, the diffusion-recombination equation. I'm interested in the long time behavior after a very short time excitation pulse. Ideally, pdsolve would have the capability to use a small time step for the initial part followed by a larger time step later. Otherwise, I could take the result of a calculation with a short time step as an initial condition for a calculation with a long time step. If anyone knows how to do either of those things, I would be grateful. Thanks, Richard

I have Maple 10.04 running on my PC. The Maplesoft product update site says Maple 10.06 update is available. Do I have to install 10.05 update first? Or can I go from 10.04 to 10.06 directly?? Thanks in advance !

## 1d phaseportrait...

Hello everybody I need to draw a phase portrait for the one-dimensional linear independent equation(just the arrows in axe X) Help me, please!!!

## Augmenting a matrix...

> Suppose I create a matrix as follows:

>

Now I want to make it a 4 x 3 matrix by adding a specific row vector on top. The approach below doesn't work.

>

## Simple question about increasing the size of a Mat...

Hi I pretty new to Maple and I have the following question. I make some calculations and out pops a number of values I am interesting. This is done several times in a loop (which I don't know the number of iterations of). Now, I would like to save these values so I can use them later on. My idea was to put everything into a matrix, and increase the size of it during runtim. I.e. initialize M for 1 to 5 do some calculations that return a and b change M so that M equals the old M with a and b added as last row end do How do I do this?

## system of nonlinear equations...

Hello, I am quite new to Maple and I am trying to solve a system of 3 non-linear equations in 3 variables (A,zp,zh). I have tried the solve command, but after waiting few hours I have decided to stop the computation. Could someone help me with this? The system is as follows eq1 := 1/(-138.8888889/(24000000-50/3*zh)^1.5-.50/zh^1.5-122.7222223/(-8640000+47/3*zh)^1.5)*(5.465600000*A/(1+zp)^.5e-1 +(-16.66666667/(24000000-50/3*zh)^.5+1.0/zh^.5+15.66666667/(-8640000+47/3*zh)^.5)*(.3e-1+.3*A))=0; eq2 := .4879000781e-6/A*(1+zp)^2.05*((-1952000.00*A/(1+zp)^1.05+50/3)*(.3e-1+.3*A)-10.93120000*A/(1+zp)^.5e-1

## Stochastic paths - Brownian motion, multiple graphs,...

by: Maple
Hi everyone, I am an undergraduate studying Stochastic Financial Modelling. I am currently writing up a simple brownian motion as shown on the attachment. I have difficulty in simulation a number of these paths and displaying 5 or so of them on the graph with the average path of all simulated paths. In this case, i would expect the average to be a straight line along the axis. Can anyone help me with this as i am only a novice in maple programming? Thanks, Steve

## Identifying an assumed variable...

Hi: In one part of my calculation, I need to assume some properties for a variable; later on, the assumption is no longer needed so I clear the variable. After that, I cannot manipulate any of the previously calculated expressions containing that same variable. Here is an example. How do I get around this? I really need to clear the variable for other reasons. Thanks Mike restart;assume(n>0); > test:=-5/81*n^5+b*n^4+c*n^3+d*n^2+e*n+f; 5 5 n~ 4 3 2 test := - ----- + b n~ + c n~ + d n~ + e n~ + f 81

## Collapse document block...

The enclosed file has 2 document blocks. As far as I can tell, each block is identical except for the name of a procedure defined in it. When I go into Block A and select Format/Collapse Document Block, the procedure does not disappear. When I go into block B, it does. I'd appreciate it if someone could tell me why the difference. -Thanks View 2292_Georgeworksheet15.mw on MapleNet or Download 2292_Georgework