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These are questions asked by digerdiga

Just wanted to ask, what the issue here is:

Int(1/(1 - x*ln(x)), x);

doesn't give the proper transformation. It gives


Solving for x and writing the transformation in terms of LambertW gives something else, if I'm not mistaken.


I have this simple problem which doesn't want to work.

d := g -> (D@@2)(g) - x^2*g;
((d@@2)(g) assuming x::constant);


The result of the last line is:

(D@@4)(g) - 2*(D@@2)(x)*x*g - 2*D(x)^2*g - 4*D(x)*x*D(g) - x^2*(D@@2)(g) - x^2*((D@@2)(g) - x^2*g)

so Maple doesn't set D(x) to 0. On the other hand if I just write

D(x) assuming x::constant

then Mapel returns 0.


D(f^k) assuming k::constant

just returns D(f^k) and not k*D(f)*f^(k-1) as the example in HELP suggests.

Hello, There seems to be a bug in the int() routine when CPV is being used i.e.

f1 := (int(t^(2*a - 1)/(-t^2 + 1), t = 0 .. infinity, CPV = true) assuming (0 < a, a < 1));

the result given is

f1 := Pi/(2*sin(Pi*a)*(-1)^(1 - a))

but the correct result is

f1 := Pi/2*cot(Pi*a).


Hello, I was wondering about the following.

cos(Pi/2^n) can be converted to a radical for each integer n, because cos(Pi/2)=0 is known and successively

cos(x)=sqrt( (1+cos(2x))/2 )

so in principle radical expressions should exist for all integers n. But maple only converts cos(Pi/8) to a radical, but not cos(Pi/16) and higher powers. Is there a simple way without writing an own program to obtain these radical expressions using convert(*,radical)?





restart; with(Physics); Setup(mathematicalnotation = true); Setup(dimension = 3, metric = Euclidean, spacetimeindices = lowercaselatin); g_[]; Define(X[i], P[k]); Setup(quantumop = {P, X}, algebrarules = {%Commutator(P[i], P[j]) = 0, %Commutator(X[i], X[j]) = 0, %Commutator(X[j], P[k]) = Physics:-`*`(I, g_[j, k])}); L2 := Simplify(Physics:-`^`(Physics:-`*`(Physics:-`*`(LeviCivita[i, j, k], X[j]), P[k]), 2)); L2X := Simplify(Commutator(L2, X[k])); L2L2X__1 := Simplify(Commutator(L2, L2X)); L2L2X__2 := Simplify(Expand(AntiCommutator(Physics:-`*`(2, L2), X[k]))); Simplify(L2L2X__1-L2L2X__2)

[mathematicalnotation = true]


`The dimension and signature of the tensor space are set to `[3, `- - +`]


`The Euclidean metric in cartesian coordinates`


`Changing the signature of the tensor spacetime to: `*`+ + +`


[dimension = 3, metric = {(1, 1) = 1, (2, 2) = 1, (3, 3) = 1}, spacetimeindices = lowercaselatin]


Physics:-g_[a, b] = Matrix(%id = 18446746397905475934)


`Defined objects with tensor properties`


{Physics:-Dgamma[a], P[k], Physics:-Psigma[a], X[i], Physics:-d_[a], Physics:-g_[a, b], Physics:-LeviCivita[a, b, c]}


`* Partial match of  '`*quantumop*`' against keyword '`*quantumoperators*`' `




[algebrarules = {%Commutator(P[i], P[j]) = 0, %Commutator(X[i], X[j]) = 0, %Commutator(X[j], P[k]) = I*Physics:-g_[j, k]}, quantumoperators = {P, X}]


(2*I)*Physics:-`*`(X[j], P[j])+Physics:-`*`(Physics:-`^`(X[j], 2), Physics:-`^`(P[k], 2))-Physics:-`*`(X[j], X[k], P[j], P[k])


2*X[k]-(2*I)*Physics:-`*`(Physics:-`^`(X[b], 2), P[k])+(2*I)*Physics:-`*`(X[c], X[k], P[c])


(12*I)*Physics:-`*`(X[c], X[k], P[c])-(4*I)*Physics:-`*`(Physics:-`^`(X[b], 2), P[k])+4*X[k]+4*Physics:-`*`(Physics:-`^`(X[b], 2), X[k], Physics:-`^`(P[h], 2))-4*Physics:-`*`(X[a], Physics:-`^`(X[b], 2), P[a], P[k])+4*Physics:-`*`(Physics:-`^`(X[b], 2), X[f], P[f], P[k])-4*Physics:-`*`(X[f], X[i], X[k], P[f], P[i])


4*X[k]+(12*I)*Physics:-`*`(X[c], X[k], P[c])+4*Physics:-`*`(Physics:-`^`(X[b], 2), X[k], Physics:-`^`(P[d], 2))-(4*I)*Physics:-`*`(Physics:-`^`(X[b], 2), P[k])-4*Physics:-`*`(X[e], X[f], X[k], P[e], P[f])









Download Commutator_Algebra_with_L2.mw




I have the following issue.

The way it is set at the moment, works kinda in that the final result is 0, which I tried to check.

However, the expression L2L2X[1] is not fully Simplified, since the term

-(4*X[a])*X[b]^2*P[a]*P[k] + (4*X[b]^2)*X[f]*P[f]*P[k]

is actually zero. I suppose that he doesn't manage because of the different indices "a" and "f" here. How can this be fixed?


When I comment out "Define" and use "Coordinates(X,P)" instead, it doesn't work. Seems to give the wrong result (Difference is not zero).


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