restart;
Digits := 10;
evalf(Int(x*(1-2*x^(3/10))^(10.*(1/3)), x = 0 .. 1))

On Windows 8.1 64 bit Maple 2017.3 64 bit - Crash

Possible duplicate. https://www.mapleprimes.com/questions/223444-Heat-Equation-Graph

@Markiyan Hirnyk 

I'm split book from page 187 to 217:Pages-187-217.pdf

@Markiyan Hirnyk 

You can download book from : http://www.if.ufrj.br/~tgrappoport/aulas/metfis2/0123747325.pdf

@_Maxim_ 

Yes You a right.   

evala(Normal(simplify(diff(int(sqrt(t^4+1)-t^2, t), t))))
# sqrt(t^4+1)-t^2

This is incorrect:

evalf(int(sqrt(t^4+1)-t^2, t = 1 .. infinity));
# -1.992145865+3.*10^(-10)*I

It should be :

#0.4799537050

Yes is a bug in int function.

expand(simplify(diff(int(sqrt(t^4+1)-t^2, t), t)));

# t^4/sqrt(t^4+1)-t^2+1/sqrt(t^4+1)

I will submit this bug to SCR.

I think is not a bug.

Try:

pdsolve([diff(u(t, x), t, t) = diff(u(t, x), x, x), u(t, 0) = 0, u(t, Pi) = 0, u(0, x) = 0]);

#u(t, x) = Sum(_C1[n]*sin(n*t)*sin(n*x), n = 1 .. infinity)

C1[n] and C2[n]  are dependent on boundaryconditions for time variable (u(T1,x)=u1,u(T2,x)=u2).

maybe I'm wrong....

@markweitzman

Eigen4 := (dsolve({bc, ode}, numeric, range = 0 .. 2, maxmesh = 8192, abserr = 1.*10^(-1), approxsoln = [y(u) = -u, e = 2]))(0)[4];
Eigen5 := (dsolve({bc, ode}, numeric, range = 0 .. 2, maxmesh = 2192, abserr = 1.*10^(-3), approxsoln = [y(u) = sin(u), e = 2]))(0)[4];

You have three conditions and two degrees of freedom. There may not be a solution.

Use:

pdsolve([Yours System-PDE]);

@vv

For Maple users it will be useful to someone and for me.

Thanks a lot :)

Mathematica also no better.

@Kitonum 

Works Fine on my system:

`Standard Worksheet Interface, Maple 2017.3, Windows 8.1, September 27 2017 Build ID 1265877`

`Maple 2017.3, X86 64 WINDOWS, Sep 27 2017, Build ID 1265877`

NO_ERROR.mw

Thanks to share a cool stuff.

Maybe you can add(improve) to calculate surface area if  it's possible.

SurfaceArea(1, [x^2+y^2+z^2 <= 1, 5*x^2-z^2 <= 1], [x, y, z])

# 6.50063

Mathematica solution:

@vv 

Yes you are right,I made a mistake.Now its work fine.

Thanks you for your feedback.