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Wolfram Alpha and Mathematica

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  • Subject: [mg101174] Wolfram Alpha and Mathematica
  • From: Andrzej Kozlowski <akoz at>
  • Date: Fri, 26 Jun 2009 06:47:58 -0400 (EDT)

As we all know the engine behind Wolfram Alpha is Mathematica, but  
there seem to be some restrictions on the kind of problems Wolfram  
Alpha is willing to solve. They do not seem to be documented and it is  
not clear whether they are based on some complexity of the problem,  
the time it takes to solve or something else. Here is a typical example.

Note that

  Expand[(1 - a^2)*(1 - b^3)]
a^2*b^3 - a^2 - b^3 + 1

now type into Wolfram Alpha:

factor a^2*b^3 - a^2 - b^3 + 1

you will get the expected factorization.

Now multiply the previous input by (1-c) and type:

factor -(a^2*b^3*c) + a^2*b^3 + a^2*c - a^2 + b^3*c - b^3 - c + 1

you will again get the expected factorization

but now replace the factor 1-c by a-c and try:

factor a^3*b^3 - a^3 - a^2*b^3*c + a^2*c - a*b^3 + a + b^3*c - c

Wolfram Alpha will tell: Wolfram|Alpha isn't sure what to do with your  

Really? So what's the great difference between this input and the  
previous ones? Moreover, you will be asked:

Are you an expert on this topic? Find out how you can help.

Common guys. You don't need my help on this topic. There is obviously  
some other reason for this, and if so I think it should be stated.

Andrzej Kozlowski

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