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Re: how to simplify Log[E^(2/3 x^(3/2))] ?


	> Can somebody tell me why

	> Log[y E^(2/3 x^(3/2))]

	> cannot be simplified by using Simplify[]?

It isn't clear what you want it to simplify to, but I might guess
that you are looking for (2/3 x^(3/2)) Log[y].  The simple
answer is that it doesn't simply to (2/3 x^(3/2)) Log[y] because
it isn't true:

In[1]:= {Log[y E^(2/3 x^(3/2))], (2/3 x^(3/2)) Log[y]}

                  3/2           3/2
              (2 x   )/3     2 x    Log[y]
Out[1]= {Log[E           y], -------------}
                                   3

In[2]:= % /. {x -> -7.0, y -> 1}

Out[2]= {0. + 0.219531 I, 0}

Jerry B. Keiper
keiper at wri.com
Wolfram Research, Inc.





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