I find that isdifferentiable is quite unreliable. E.g.:

restart:
piecewise(t < t0, 0, (6*(t-t0))^(3/2)):
isdifferentiable(%,t,1);

                                 true

restart:
piecewise(t < t0, 0, (6*t-6*t0)^(3/2)):
isdifferentiable(%,t,1,'v');v;

                                false

                              -1, {-t0}

For the latter output, ?isdifferentiable states:

The optional argument varparam can be passed to the function and in case expr is not of class C^n , varparam contains information of which C^n class the function is, and a list of points where we have discontinuities in the n+1-th derivative.

I find this sentence rather confusing, but my interpretation of the above output goes like the input function is of class C^(-1), presumably meaning that it is not continuous at t=-t0 but its integral is.

I observe that these problems occur from Maple 11.02 on (no such problems in Maple 10.06).

Edit: In this particular example, the cache seems to be a key issue:

restart:
piecewise(t < t0, 0, (6*(t-t0))^(3/2)):
isdifferentiable(%,t,1);

                                 true

forget(isdifferentiable);
piecewise(t < t0, 0, (6*t-6*t0)^(3/2)):
isdifferentiable(%,t,1);

                                 true

I think that the properties attached to some function names (and those deducible from them) intend to describe these mathematical functions globally over the real line. E.g. here:

`property/object`[exp];

  AndProp(unary, StrictlyMonotonic, InfinitelyDifferentiable, Non(constant))

the property StrictlyMonotonic makes sense only in this context.

I think that the properties attached to some function names (and those deducible from them) intend to describe these mathematical functions globally over the real line. E.g. here:

`property/object`[exp];

  AndProp(unary, StrictlyMonotonic, InfinitelyDifferentiable, Non(constant))

the property StrictlyMonotonic makes sense only in this context.

As far as I understand it, the reason is that the development of the Classic GUI is frozen (except perhaps for some critical bug fixing). Meaning, in particular, that it will stay as a 32 bit application and no 64 bit version will be developed. Note also that the Classic help pages are no longer available in Maple 14.

Nevertheless, "recipes" were posted for using the Classic GUI under 64 bit Linux and Windows.

As far as I understand it, the reason is that the development of the Classic GUI is frozen (except perhaps for some critical bug fixing). Meaning, in particular, that it will stay as a 32 bit application and no 64 bit version will be developed. Note also that the Classic help pages are no longer available in Maple 14.

Nevertheless, "recipes" were posted for using the Classic GUI under 64 bit Linux and Windows.

So, the next step would be saving/printing the main content of the whole thread to "clean" text (or printer-friendly html format at least).

@acer 

Indeed, the bad typesetting results of my tests of the "Maple Math" method for posting output have convinced me to avoid it: I find that even the "primitive" 2-D ascii math looks better in most cases.

In general, I do skip most of the posts using the worksheet-upload method as usually I do not have time nor patience to retype the input or download-launch the Standard GUI, and copy-paste the input into 1-D (actually into Classic).

I also tend to skip blogs when I see them laden with 2-D math gif files as their transfer time is too long.

It works nice in Classic using plotsetup(maplet).

It works nice in Classic using plotsetup(maplet).

@Axel Vogt 

I use a customized style set mw file in Standard GUI: Format > Manage Style Sets > User-defined Style Set. May be you need to create one?

@Axel Vogt 

I use a customized style set mw file in Standard GUI: Format > Manage Style Sets > User-defined Style Set. May be you need to create one?

@chengran 

So, you will get better advice by posting the actual integral. A priori, if these long expressions are independent of the integration variable, you could use Maple also to substitute them for symbols like B, C, D, integrate as you already know, and backsubstitute the symbols in the final expression.

@chengran 

So, you will get better advice by posting the actual integral. A priori, if these long expressions are independent of the integration variable, you could use Maple also to substitute them for symbols like B, C, D, integrate as you already know, and backsubstitute the symbols in the final expression.

Mathematica 7 produces this result for the quartic case:

In[1]:= Integrate[Exp[-B*y^4 - C*y^2]*y^3, {y, D, Infinity}, 
Assumptions -> {B > 0, C > 0, D > 0}]

                         2 2                              2
               (C + 2 B D ) /(4 B)               C + 2 B D
            C E                    Sqrt[Pi] Erfc[----------]
                                                 2 Sqrt[B]
        2 - ------------------------------------------------
                                Sqrt[B]
Out[1]= ----------------------------------------------------
                               2         2
                              D  (C + B D )
                         8 B E

I do not know what algorithm or heuristics is used here.

Mathematica 7 produces this result for the quartic case:

In[1]:= Integrate[Exp[-B*y^4 - C*y^2]*y^3, {y, D, Infinity}, 
Assumptions -> {B > 0, C > 0, D > 0}]

                         2 2                              2
               (C + 2 B D ) /(4 B)               C + 2 B D
            C E                    Sqrt[Pi] Erfc[----------]
                                                 2 Sqrt[B]
        2 - ------------------------------------------------
                                Sqrt[B]
Out[1]= ----------------------------------------------------
                               2         2
                              D  (C + B D )
                         8 B E

I do not know what algorithm or heuristics is used here.