sursumCorda

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My questions are then, is there a way to get Maple to solve this? 

Yes, there is a way: 
 

restart

Warning, inserted missing semicolon at end of statement

 

simplify(eval(student['changevar'](u = sqrt(sqrt(x^4+1)+x^2), int(sqrt(sqrt(x^4+1)+x^2)/((x+1)*sqrt(x^4+1)), x), u), u = sqrt(sqrt(x^4+1)+x^2)), 'size' = true, assume = negative)
NULL

(1/4)*2^(1/2)*(2*(2^(1/2)-1)^(1/2)*arctan(((x^4+1)^(1/2)+x^2)^(1/2)/(2^(1/2)-1)^(1/2))+(2^(1/2)-1)^(1/2)*arctan((1/2)*((2^(1/2)-1)*(x^4+1)^(1/2)+2^(1/2)*x^2-x^2+1)/((2^(1/2)-1)^(1/2)*((x^4+1)^(1/2)+x^2)^(1/2)*x))-2*(1+2^(1/2))^(1/2)*arctanh(((x^4+1)^(1/2)+x^2)^(1/2)/(1+2^(1/2))^(1/2))+(1+2^(1/2))^(1/2)*arctanh((1/2)*(2^(1/2)*x^2+(x^4+1)^(1/2)*2^(1/2)-1+x^2+(x^4+1)^(1/2))/((1+2^(1/2))^(1/2)*x*((x^4+1)^(1/2)+x^2)^(1/2))))

(1)

radnormal(diff((1/4)*2^(1/2)*(2*(2^(1/2)-1)^(1/2)*arctan(((x^4+1)^(1/2)+x^2)^(1/2)/(2^(1/2)-1)^(1/2))+(2^(1/2)-1)^(1/2)*arctan((1/2)*((2^(1/2)-1)*(x^4+1)^(1/2)+2^(1/2)*x^2-x^2+1)/((2^(1/2)-1)^(1/2)*((x^4+1)^(1/2)+x^2)^(1/2)*x))-2*(1+2^(1/2))^(1/2)*arctanh(((x^4+1)^(1/2)+x^2)^(1/2)/(1+2^(1/2))^(1/2))+(1+2^(1/2))^(1/2)*arctanh((1/2)*(2^(1/2)*x^2+(x^4+1)^(1/2)*2^(1/2)-1+x^2+(x^4+1)^(1/2))/((1+2^(1/2))^(1/2)*x*((x^4+1)^(1/2)+x^2)^(1/2)))), x)-sqrt(sqrt(x^4+1)+x^2)/((x+1)*sqrt(x^4+1)));

0

(2)

int((-7+x)/((-11+5*x)*sqrt(x^4-3*x^3-21*x^2+83*x-60)), x, 'method' = 'Trager')NULL

radnormal(diff((1/3)*sqrt(2/3)*arctanh(-3*sqrt(3/2)*(x-1)*(x-3)/sqrt((x+5)*(x-1)*(x-3)*(x-4))), x)-(-7+x)/((-11+5*x)*sqrt(x^4-3*x^3-21*x^2+83*x-60)))

-(1/18)*RootOf(_Z^2-6)*ln(-(29*RootOf(_Z^2-6)*x^2-106*RootOf(_Z^2-6)*x+41*RootOf(_Z^2-6)+36*(x^4-3*x^3-21*x^2+83*x-60)^(1/2))/(-11+5*x)^2)

(3)


 

Download Don't_Forget_Integrals!.mw 
Compare:

I wonder why by default Maple is unable to calculate the second antiderivative mentioned in the link given by the OP (Note that the substitution x = 3 - 1/(t - 1/8) can reduce some degree.) in terms of elementary functions. According to Integration Methods - method=pseudoelliptic, now Maple is capable of integrating it heuristically, but here Maple simply fails to do so (unless using method=Trager (yet the result is still less nice)).  (Besides, Mathematica is also rumored to discover human-friendly solutions to the so-called pseudo-elliptic integrals: https://github.com/stblake/algebraic_integration.)

restart;
_seed := 1234:
Warning, the use of _seed is deprecated.  Please consider using one of the alternatives listed on the _seed help page.
M := LinearAlgebra:-RandomMatrix(4, 'generator' = 0 .. 1., 'datatype' = float[4]);
st := time():
linalg:-exponential(M, -I*t):
time() - st;
                             0.141

st := time():
:-LinearAlgebra:-MatrixExponential(M, -I*t):
time() - st;
                             1.828

M := LinearAlgebra:-RandomMatrix(8, 'generator' = 0 .. 1., 'datatype' = float[4]);
st := time():
linalg:-exponential(M, -I*t):
time() - st;
                             4.219

st := time():
:-LinearAlgebra:-MatrixExponential(M, -I*t):
time() - st;
                             24.594

So the LinearAlgebra package does not always seem to be more powerful and efficient in doing linear algebra calculations?!

In theory, this should be a workaround: 

restart;
use MmaTranslator:-Mma in MapAll(Chop, 1.378834798932344e-15*I*t) end;
# Nevertheless, it does not work as expected. 
Error, (in MmaTranslator:-Mma:-MapAll) too many levels of recursion

But strangely, this works well: 

use MmaTranslator:-Mma in map(Chop, 1.378834798932344e-15*I*t) end use;
 = 
                               0

Though @acer's approach works here, the MmaTranslator:-Mma subpackage does not seem to allow us to go beyond the basics.

You may have to use: 

restart;
(proc(` $`)
	local `&*`;
	redefine(`&*`, ['associative']); # Regretfully, “setattribute(`&*`, 'associative');” does not work here.
	use `*` = `&*` in
		local expr := -(r0+Delta_r)^2*(46*r0-41*Delta_r)*r0^5;
		subsop(1=a,2=b,3=c,4=d, expr)
	end;
	eval(`%`, `&*` = `*`)
end)() = 
                            a b c d

The key is 'associative' (instead of `&*`). 

Another way may be 

DETools:-DEplot(diff(y(x), x) = abs(1/sqrt(1 - x^2)), y(x), x = -.99 .. .99, y = -1.6 .. 1.6, [y(0) = 0], 'arrows' = 'fish'):

According to the help page, “If the third argument n is present then it specifies the "truncation order" of the series calculations”, so you may simply use: 

series(BesselK(4, x), x = 0, 0);
                       (-4)      (-2)    / 0\
                   48 x     - 4 x     + O\x /

 

To avoid explicit "*" or "·", I think that you can use 

subs("⋅" = " ", InertForm:-Display((* an inert-form expression *), 'inert' = false));

As for the second point, maybe you can use 

Sol2 := InertForm:-Display((`%/`@`?[]`@[primpart*numer, denom]*primpart)( Sol2 ), 'inert'=false):

 

How about

(convert~)~(convert~(convert(x*y*z*z*w*w*w, list, `+`), list, `*`), list, `^`);
 = 
               [[[x, 1], [y, 1], [z, 2], [w, 3]]]

?

According to the documentation of Cmd.exe, if the directory path, files, or any information you supply contains spaces, you must use double quotation marks around the text. So a potential workaround is: 

restart; kernelopts(opaquemodules = false):
Compiler:-Build:-buildVarDB["X86_64_WINDOWS"]["LDLIBS"] := StringTools:-RegSubs(StringTools:-Join([convert(curry(sprintf, "(%s%s.*%s)"), function, StringTools:-Escape~([kernelopts('bindir'), kernelopts('dirsep'), ".lib"], 'regexp')) $ 3], " ") = "\"1\" \"2\" \"3\"", Compiler:-Build:-buildVarDB["X86_64_WINDOWS"]["LDLIBS"]()):
# Thereafter `Compiler:-Compile` will work. 

I am not sure if this works on your computer, but at least this works for me.
Note that on Windows platforms, the default external C++ compiler distributed with Maple is Clang, so one can download the latest release of the LLVM-based MinGW and then replace the subfolder $MAPLE_ROOT/llvm manually. 
 

restart;

interface(verboseproc = 0):

p := proc (x::float)::float: options trace: 2.3*x end:

cp := Compiler:-Compile(p)

Warning, inserted missing semicolon at end of statement

 

Error, (in Compiler:-Compile) compiler exited with nonzero status 1:

 

assigned(cp);

false

(1)

kernelopts(opaquemodules = false):

Compiler:-Build:-buildVarDB["X86_64_WINDOWS"]["LDLIBS"] := StringTools:-Join(String~("\"", Compiler:-Tools:-fullPath~(Compiler:-Tools:-pathCat~(kernelopts(':-bindir'), ["mrt.lib", "libhf.lib", "maple.lib", NULL])), "\""), " "):

cp := Compiler:-Compile(p);

proc () options call_external, define_external(maple_compiled_me7bd84bdbb60a2956a493cad724f8039, MAPLE, LIB = "C:\Users\ACER\AppData\Local\Temp\ACER-15036\maple_compiled_me7bd84bdbb60a2956a493cad724f8039yx7CnQC9.dll"); call_external(0, 140736776377376, true, false, false, args) end proc

(2)

cp(1e1);

{--> enter p, args = .1e2

 

23.

(3)

 


 

Download 236724-How-Can-I-Get-The-Compiler-To-Work.mw

This also works:

bound := 0:
do until SMTLIB['Satisfiable'](And(
      (154*x + 69*y) - 0 = 7**3*m1, 
      (13*x + 716*y) - 0 = 13**3*m2, 
     (23*x + 3059*y) - 0 = 23**3*m3, 
         x > 0, x < y, y = ++bound), 
                 'logic' = "QF_LIA"):
bound;
 = 
                             18837

Unfortunately, it takes several minutes to solve on my low-end PC.
That may fell a bit slow, yet the human time required to code a faster algorithm is a lot longer than several minutes and perhaps longer than one care to wait.

Edit. Of course the original problem can be reformulated as an integer linear program, but to the best of my knowledge, none of "exact" solvers are integrated into (and accordingly, are unable to take advantage of) modern computer algebra systems. (Actually, when I search for this term, I can only find exact SCIPExact, QSopt_ex and SoPlex, which are all irrelevant to a CAS that is capable of carrying out computations analytically.) Alas, what a pity!

If I understand right, "[x^2-x*y, x*y-y^2, x*z-y*z, -x^2+y^2, x*y+x*z]" can be obtained as follows: 

convert(expand({eval(MmaTranslator:-Mma:-Distribute([x - y]*[x, y, z], list, `*`), list = expand@``), -x^2 + y^2, x*y + x*z}), list);
 = 
      [       2    2    2   2                            ]
      [x y - y , -x  + y , x  - x y, x z - y z, x y + x z]

And "[x^3-x^2*y, x^2*y-x*y^2, x^2*z-x*y*z, x*y^2-y^3, x*y*z-y^2*z, x*z^2-y*z^2, -x^3+x*y^2, -x^2*y+y^3, -x^2*z+y^2*z, x^2*y+x^2*z, x*y^2+x*y*z, x*y*z+x*z^2, -x*y*z+z^3, x*y^2+y*z^2-z^3]" can be obtained as follows: 

convert(expand({eval(MmaTranslator:-Mma:-Distribute([x^2 - x*y, x*y - y^2, x*z - y*z, -x^2 + y^2, x*y + x*z]*[x, y, z], list, `*`), list = expand@``), -x*y*z + z^3, x*y^2 + y*z^2 - z^3}), list);
 = 
  [   2    3    2      3   2        2    3      2   3    2    
  [x y  - y , -x  y + y , x  y - x y , -x  + x y , x  - x  y, 

       2      2            3           2               2  
    x z  - y z , -x y z + z , x y z - y  z, x y z + x z , 

       2            2      2     2             2      2    
    x y  + x y z, -x  z + y  z, x  z - x y z, x  y + x  z, 

       2      2    3]
    x y  + y z  - z ]


 

@minhthien2016 Alternatively, 

subs('y' = 1, collect('y' * ~ [exp1, exp2], x, normal));
 = 
[ 3              2                 3            2              ]
[x  + (3 m - 1) x  - (4 m + 3) x, x  + (m + 1) x  + (4 m + 3) x]

 

solve('identity'(aa/f^bb = 1.234/(f^6.789), f), {aa, bb});
 = 
              {aa = 1.234000000, bb = 6.789000000}

PDETools:-Solve(aa/f^bb = 1.234/(f^6.789), {aa, bb}, 'independentof' = f);
 = 
              {aa = 1.234000000, bb = 6.789000000}

match/patmatch/typematch also works.

For some unknowable reason, Maple cannot fully simplify the L. Fortunately, a workaround exists: 
 

restart;

L__0 := inttrans['laplace']((t+1)/sqrt(t^2+2*t), t, p)

(1/2)*(Pi^(1/2)*WhittakerW(-1/2, 1/2, 2*p)/p+2*BesselK(0, p))*exp(p)

(1)

L__1 := simplify(convert(L__0, KummerU), size)

Pi^(1/2)*(KummerU(1/2, 1, 2*p)+KummerU(3/2, 2, 2*p))

(2)

L__2 := subs(KummerU(3/2, 2, 2*p) = -(Diff(KummerU(1/2, 1, 2*p), p)), KummerU(1/2, 1, 2*p) = exp(p)*BesselK(0, p)/sqrt(Pi), L__1)

Pi^(1/2)*(exp(p)*BesselK(0, p)/Pi^(1/2)-(Diff(exp(p)*BesselK(0, p)/Pi^(1/2), p)))

(3)

L__3 := simplify(value(L__2))

exp(p)*BesselK(1, p)

(4)

smartplot(L__3-L__0)

 


 

Download 236850-How-To-Get-A-Simpler-Expression-Of-The.mw

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