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The following limit does not return a value. Then the evalf gives a wrong answer.

The answer should be "undefined" or -infinity .. infinity.

limit(exp(n)/(-1)^n, n = infinity) assuming n::posint; evalf(%);


                       /exp(n)              \
                  limit|------, n = infinity|
                       |    n               |
                       \(-1)                /

                               0.

The same happens if you delete the assumption.

 

A similar problem occurs with

limit(sin(Pi/2+2*Pi*n), n = infinity) assuming n::posint;
                            -1 .. 1
without the assumption this would be appropriate.

Why does the following statement not evaluate, or better yet, how can I make it do so?

 

A:=value(floor(p)) assuming p>0,p<1,p::real;

or

A:=simplify(floor(p)) assuming p>0,p<1,p::real;

or any one of a lot of different attempts along the above lines, all of which seem (to me) that they should yield

A:=0

rather than

A:=floor(p)

which is what I get.

Thanks in advance

``

-(-2*N__1*`&omega;__2`*`&omega;__1`^2*lambda-8*N__2*lambda^3*`&omega;__2`-sqrt(4*N__1^2*lambda^2*`&omega;__1`^2*`&omega;__2`^2+16*N__1*N__2*lambda^4*`&omega;__2`^2+N__1*N__2*`&omega;__1`^2*`&omega;__2`^4+4*N__2^2*lambda^2*`&omega;__2`^4)*`&omega;__1`)/(4*N__1*lambda*`&omega;__1`^2*`&omega;__2`+16*N__2*lambda^3*`&omega;__2`)

-(-2*N__1*`&omega;__2`*`&omega;__1`^2*lambda-8*N__2*lambda^3*`&omega;__2`-(4*N__1^2*lambda^2*`&omega;__1`^2*`&omega;__2`^2+16*N__1*N__2*lambda^4*`&omega;__2`^2+N__1*N__2*`&omega;__1`^2*`&omega;__2`^4+4*N__2^2*lambda^2*`&omega;__2`^4)^(1/2)*`&omega;__1`)/(4*N__1*lambda*`&omega;__1`^2*`&omega;__2`+16*N__2*lambda^3*`&omega;__2`)

(1)

`assuming`([simplify(-(-2*N__1*`&omega;__2`*`&omega;__1`^2*lambda-8*N__2*lambda^3*`&omega;__2`-(4*N__1^2*lambda^2*`&omega;__1`^2*`&omega;__2`^2+16*N__1*N__2*lambda^4*`&omega;__2`^2+N__1*N__2*`&omega;__1`^2*`&omega;__2`^4+4*N__2^2*lambda^2*`&omega;__2`^4)^(1/2)*`&omega;__1`)/(4*N__1*lambda*`&omega;__1`^2*`&omega;__2`+16*N__2*lambda^3*`&omega;__2`), 'size')], [all, positive])

(1/4)*(4^(1/2)*((N__1*lambda^2+(1/4)*N__2*`&omega;__2`^2)*`&omega;__2`^2*(N__1*`&omega;__1`^2+4*N__2*lambda^2))^(1/2)*`&omega;__1`+2*lambda*`&omega;__2`*(N__1*`&omega;__1`^2+4*N__2*lambda^2))/(lambda*`&omega;__2`*(N__1*`&omega;__1`^2+4*N__2*lambda^2))

(2)

`assuming`([combine((1/4)*(4^(1/2)*((N__1*lambda^2+(1/4)*N__2*`&omega;__2`^2)*`&omega;__2`^2*(N__1*`&omega;__1`^2+4*N__2*lambda^2))^(1/2)*`&omega;__1`+2*lambda*`&omega;__2`*(N__1*`&omega;__1`^2+4*N__2*lambda^2))/(lambda*`&omega;__2`*(N__1*`&omega;__1`^2+4*N__2*lambda^2)), 'size')], [N__1 > 0, N__2 > 0, `&omega;__1` > 0, `&omega;__2` > 0, lambda > 0])

(1/4)*(`&omega;__1`*`&omega;__2`*((4*N__1*lambda^2+N__2*`&omega;__2`^2)*(N__1*`&omega;__1`^2+4*N__2*lambda^2))^(1/2)+2*lambda*`&omega;__2`*(N__1*`&omega;__1`^2+4*N__2*lambda^2))/(lambda*`&omega;__2`*(N__1*`&omega;__1`^2+4*N__2*lambda^2))

(3)

 

``

``


Download question_13.12.06.mw

Hello,

I got problem with assuming and solve.

`assuming`([solve(abs(-2*r*(-1/2)*(1+sqrt(1+4*r))/r)<1)],[r>-1/4]);

There is nothing happens... Neither solution or some errors

What am I doing wrong?

I have a situation

restart:
with(IntegrationTools):
with(PDEtools):
declare(w(r));
assume(delta::constant, R::constant, K:: constant, U::constant):
ODE_1:=diff(w(r),r)+R*(diff(w(r), r))^3-K/r;
 
declare(u(r));
ODE_T_1:=collect(algsubs(w(r)=u(r)+(r-1)*(U-0)/(delta-1), ODE_1),diff(u(r), r)) ;
eq1:=int(phi[i](r)*ODE_T_1,r=1..delta) assuming delta > 1;
eq2:=Expand(eq1);
eq3 := applyop(u->Parts(u,phi[i...

Hi all,

I have the following functions.

restart:
with(IntegrationTools):
N:=4:

i:='i':
for i from 1 to N do
assume(x[i-1]::constant):
assume(x[i+1]::constant):
assume(x[i-1]::constant):
assume(h::constant):
 phi[i](t):=piecewise(t>=x[i-1] and x[i]>t, (t-x[i])/(h), x[i]
(x[i+1]-t)/(h), 0);
end do;
## my goal is solve the integrals involving phi[i]'s as integrand and x[i]'s as its limits.

This example was reported to me after a Calculus II student encountered this ridiculous result:

f := (k+5)/sqrt(k^7+k^2):
Int( f, k=1..infinity ):
% = value( % );
/infinity
| k + 5
| -------------- dk = -infinity
| (1/2)
/1 / 7 2\
\k + k /

Dear Maple Users,

I'm solving quite a complicated task, so I tried to simplified an example.

There is an equation:

SOL := fsolve(Nz+int(int(StrssCctXY(x, y), x = -(1/2)*b .. (1/2)*b), y = -(1/2)*h .. (1/2)*h) = 0, {C1 = -(1/2)*h .. (1/2)*h})

 StrssCctXY(x,y) is piecewise function containing C1 variable, to solve an equation I had to use assumptions on C1 via assume(C1<num1, C1>-num2) command, after that C1 becomes C1~;

 

can you explain me when i solve equation beta-t*beta=0 with condition beta<>0. I write command:
r :=solve(beta-t*beta, t, UseAssumptions), assuming beta <> 0
It works well. But it will be a problem when command is:
r :=solve(beta-t*beta, t, UseAssumptions), assuming beta <> 0, gamma<>0;
Error: Error, (in assuming) when calling 'assume'. Received: 'cannot assume on a constant object'.
thank you very much.

How can I most succinctly and straightforwardly get Maple to simplify f below to g below?

> f:=(6*x^2-6*x+6)^(1/2)*(2*x^2-2*x+2)^(1/2);

                          (1/2)                 (1/2)
          /   2          \      /   2          \     
          \6 x  - 6 x + 6/      \2 x  - 2 x + 2/     

> g:=simplify(f) assuming x::real;

                        (1/2) / 2        \
                     2 3      \x  - x + 1/

> simplify(g-f...

I need maple to perform the following:

"int((1+m^2*(alpha-theta)^2*sin(theta)^2/sin(alpha)^2/alpha^2)^(1/2),theta = 0 .. alpha)"

but maple does not integrate. I have tried assuming that the term inside the square root is positive, with no result. What else can I do?

I really need a result to the integration below but Maple 13 just won't return one. Could you please help me or advise me as to what might be wrong or what I might try ? I'm integrating on the real line in x but even when I alter the limits of integration maple just returns the integrand.

 

s1:= int((1/8)*sqrt(2)*exp((1/2)*k^2*cos(x)^2/sigma^2)*exp(-(1/2)*k^2/sigma^2...

Please help me to make sense of the ways to use the simplify function. In this particular case Maple does some computation and gives me some huge output which I paste below. When I try to simplify the huge output Maple just hangs. But if I use varied commands of simplify detailed below such as simplify(huge_output,symbolic)  or  simplify(huge_output,size)  Maple gives me an output but none of the output are equal to each other and I also noticed that in one instance...

Why does this happen to Maple 15?

    `assuming`([sum(k*p*Beta(k, p+1), k = 1 .. infinity)], [p > 1]); eval(%, p = 2)

Is it possible to show with Maple that for any real p>1 the series converges to p/(p-1), e.g.,

    `assuming`([sum(k*p*Beta(k, p+1), k = 1 .. 1000)], [p > 1]): subs(p = 2, %): evalf(%)

How do I show this symbolically? Thanks.

In the following examples I attempt to remove integer multiples of Pi from sin/cos. Nothing works.

Why? How do I make it work?

Thank you.

 

term1:=cos(Pi*(3*a-2*n));
> term2:=cos(3*Pi*a+2*Pi*n);
> term3:=cos(3*Pi*a-2*Pi*n);

                     term1 := cos(Pi (3 a - 2 n))


       ...

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