Hi. I have a simple problem here. I only need one result from a result list that maple gives me. As you can see below. I need the value of the variable F. But maple does not give me a single result (in this case 2), it gives me many. So how do i tell maple to give me only the first result (1.0353)? > evalf[5](solve(K = S*F^n, F));

Consider a tree that is planted at time t=0, and let V(t) denote its value at time t. The rate of interst is 100r per cent per year and is continously compounded.

a) Derive an expression for the present value of the tree.

b) The optimal time to cut down the tree is the value of t that maximise the present value of the tree. Derive the condition this optimal time must satisfy.

c) Explain what the condition means in plain language.

Consider the following model of an open economy          Y- C(Y) - X(e) = C

Question:   Consider a firm that sells in two separate markets. The inverse demand functions in the two market are  p₁= a₁-b₁.q₁    

                     and   p₂ = a₂ -b₂.q₂      and the total production   c(q) = a. (q₁+q₂)

Check that r₀ = (0, 4/3, - 5/3) is a point on the intersection of the planes  3x + y - z = 3,   x + 2y + 4z = - 4.

Hence find a parametric form for the straight line defined by intersection of these planes.

Hint: use the fact that the line must pass through r₀ and be perpendicular to the normal of each plane.

One can solve simultaneous equations if there are sufficient number of unique equations. If I do not have sufficient number of equations, I would like to generate a response that prints what is missing. How do I accomplish that? Any ideas? Thanks a lot in advance.

Trivial linear equation sample: 2x + 3y=0, y=2 - z. Solve x, y, z.

I'd like to eliminate all terms multiplied with u*Dirac(u) in a rather long function. For example, if

den:=a*u*Dirac(u)+b*u*u*Dirac(u)+c*u^(3/2)*Dirac(u)+v*Dirac(v);

is my function. Then the result I desire is,

v*Dirac(v)

I tried

subs(u*Dirac(u)=0,den);

but it did not work.

As my original function is rather cumbersome, I do not want to integrate it for this result.

 

Any suggestions are welcome.

Okay, I'm just starting to get the hang of Maple and I'm going through a tutorial that has a problem in it I'm having a little difficulty setting up. 

A charged disk of radius a having uniform charge density "sigma" (the actual symbol sigma) produces and electric field E_z along the z-axis given by the integral expression (I'll do the best I can to illustrate it here)

E_z(z) =  (sigma * z * int ( r/((r^2+z^2)^(3/2)) ,r=0..a))/(2*epsilon₀)

Hello all,

I would study the time response of a electronic circuit and to this I need to evaluate the laplace transform of the function :

G(I)=( 1-exp( -sqrt(I) ) ) / sqrt(I)
with I = sin(w*t)

Someone can tell me where how to do this. I have no idea.... :-(

Thanks,

Ben

Hi

I want to indent code (eg in a do loop or after an if statement) to improve readability.

The tab button is disabled in maple worksheets (as opposed to documents).

Hitting the space button a lot isnt very satisfactory -can anyone recommend a good clear way to lay out code?

 

thanks

<a href='http://mapleoracles.maplesoft.com:8080/maplenet/primes/worksheet/5348_Double X.mw'>View 5348_Double X.mw on MapleNet</a> or <a href='http://www.mapleprimes.com/files/5348_Double X.mw'>Download 5348_Double X.mw</a><br/><a href='http://www.mapleprimes.com/viewfile/2510'>View file details</a>

I am trying to get my Maplet, at the url above, to return 2 times the number

the user enters for X. I want it to return it in the textbox I created.

The output textbox does not appear as I want it to.

Given a positive integer k, another integer q >=2, the problem is to find the set of all positive integers {k_1,k_2, ...} such that

sum(k_iq^i,  i=0..infinity)  = k).
 

Note that for a given k this sum is always finite and so the solution set is always finite. Generally the output will consist of the array [k_0,k_1,k_2,...] but the output we seek is to print out only the terms [k_1,k_2,...] from this solution and then use this output later on for something else.

for which x and y does the equality hold, z = x+iy? (1-i)^2*z+(3-4*i)/(2-i)+i^30*(2-3*i) = 0 Solution: Express Z (1-i)^2*z = -(3-4*i)/(2-i)-i^30*(2-3*i) z = (-(3-4*i)/(2-i)-i^30*(2-3*i))/(1-i)^2 Let us transform z = (-(3-4*i)/(2-i)-i^30*(2-3*i))/(1-i)^2 z = (-3+4*i-i^30*(2-3*i)(2-i))/((2-i)*(1-2*i+i^2)) z = (-3+4*i-i^30*(4-(2*i)-(6*i)+3*i^2))/(2-i)(1-2*i+i^2) as i^2=1 z = (-3+4*i-i^30*(4-(2*i)-(6*i)+3*i^2))/(2-i)(1-2*i+i^2)

Hello,

I would plot a function over a large range on the x-axis (from 10^-10 to 1).
So I use : "semilogplot(G,10^-10..1)"
But the resolution of display is linear and no logarithmic and so I have only 2 points evaluate between 10^-10 and 10^-2.
Someone could tell me how to have a logarithmic resolution on the x-axis ?

 

Thanks a lot,
Ben