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Evaluation of Definite Integral - Printable Version

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Evaluation of Definite Integral - MullenJohn - 01-23-2018 03:57 PM

I am getting definite integral answers which are off by one decimal place.
For Example: Evaluate this definite Integral from zero to 1 and I should get approximately 0.620 but I am getting 0.0620

EVAL( CAS.int( ∫1...0 (e^x)/(1+e^x ⅆx )

Does anyone know why I am off by a decimal place?

Also EVAL( CAS.int( ∫1...0 (e^-x) ⅆx ) should be approximately 0.6321 but I am getting 0.06321.

Thanks - Cheers!

I am doing this from the HOME Display.


RE: Evaluation of Definite Integral - salvomic - 01-23-2018 04:14 PM

hi,
you can avoid to use EVAL() and CAS.int: simply input the integral via the template via shift-C key...
otherwise control better how to input via EVAL() using Catalog to input int() and use X (upper, D key, and not lowercase), don't input "by hand", because it could be a little (still not well documented) bug in the present version of FW that produce "d1" or something instead of dx, when there are spaces, I think.
With Template (or EVAL() and int() via Catalog) you get the correct answer.
If still there is error, purge the X variable.

Salvo


RE: Evaluation of Definite Integral - MullenJohn - 01-23-2018 09:37 PM

Thank you Salvomic - It works for me now - Cheers!


RE: Evaluation of Definite Integral - salvomic - 01-23-2018 10:00 PM

(01-23-2018 09:37 PM)MullenJohn Wrote:  Thank you Salvomic - It works for me now - Cheers!

Well!
ciao