Dear Luigi
Look at the plot of your f
f:(x^2*(x+3))^(1/3);
plot2d([f], [x,-5,5])$
It can then be interesting to look at
Rf: realpart(f);
If: imagpart(f);
plot2d([Rf,If], [x,-5,5])$
This can help you to see what is going on. The x=-3 point is a very interesting one.
________________________________________________________________
Jose Sanchez-Marin.
Universitat de Valencia.
Institut de Ciencia Molecular (ICMol).
Cat. Jose Beltran Martinez, 2 Phone: +34 96 354 4444
E-46980 Paterna FAX: +34 96 354 3576
Spain e-mail: Jose.Sanchez at uv.es
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