@Christopher2222

Update intsolve to solve linear and non-linear integro-differential , systems and integral equation,systems for symbolic and numeric.

@Christopher2222

Update pdsolve ,numeric to solve partial differential equations for three,four(and more) independent variables.

And solve elliptic PDEs. It's been seven years now and Maple is still standing still.

Very briefly: Maple dosen't know the answer.

More info in Documentation:

?DESol

@Rouben Rostamian  

Mathematica better handle multidimensional integrals numerically than Maple :)

Harder  example:

Int(exp(-b^4-c^4-a^3), [a = b^2/(4*c) .. infinity, c = 0 .. infinity, b = -infinity .. infinity]);

#?

My workaround dosen't work very fast now, Maple calculations never ending.

MMA solve with about 2.88451 second.

@vv 

Oh, Yes my silly mistake.With correction answers are the same. 

Thanks.

@vv 

About volume, Mathematica gave me a different results:

@Ronan 

I2 := 2;

Optimization:-NLPSolve(I2*(I3-I1)/((I3-I2)*(I2-I1)), {I1+I2 >= I3, 0 <= I1, I1 <= I2, I2 <= I3}, assume = nonnegative);

#[Float(infinity), [I1 = 1., I3 = 2.]]

It's seems Maple FAILS in this case I3 = 2 ?

@rlopez 

Thanks for explanation.

Simulation in  MMA and another stuff.

@ecterrab 

It means that pdsolve is design to not solving PDE with weak solution?

Answer is simple, Maple is not a magic box that'll spit out a solution to any problem.

https://www.12000.org/my_notes/pde_in_CAS/pde_in_cas.htm

Probably  tripel integral is equal to Zero. My crystall ball that says.

Where is the integral ?

What have you tried?

@vv 

Workarounds always exist,but disgust always remains.

Thanks.