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Re: Indefinate integrals, erroneus Natural log?

• To: mathgroup at smc.vnet.net
• Subject: [mg77895] Re: Indefinate integrals, erroneus Natural log?
• From: Szabolcs <szhorvat at gmail.com>
• Date: Tue, 19 Jun 2007 06:39:42 -0400 (EDT)
• Organization: University of Bergen
• References: <f55oor$j6f$1@smc.vnet.net>

David Rees wrote:
> Hi,
> 
> In preparation for a major exam tomorrow, I was just checking some of my 
> answers to past-papers with mathematica, I fed it this input:
> 
> In[117]:=
> \!\(\[Integral]\((xE\^\(2 x\))\) \[DifferentialD]x\)
> Out[117]=
> \!\(xE\^\(2\ x\)\/\(2\ Log[xE]\)\)
> 
> I marked myself wrong and moved on to the next question, but I happened 
> accross the actual mark-scheme which said I was correct. It gave this 
> answer:
> 
> ((1/2)xE^(2x))-(1/4)e^(2x)
> 
> My Integral calculus isn't so strong, so I don't know if the additional 
> natural log should be there, or if the two expressions are identical.
> 
> Thanks

xE, written without a space, is the name of a single symbol, while x E, 
with a space, is x*E (the product of x and E).

Insert the missing space and you will get the result you expect.