Re: Can I solve these integrals?

"Jerzy Karczmarczuk" wrote

>So, according to 'Peltio' int(sin(x),x=0 .. PI) cannot be exactly
>computed, since it involves sin?

The spirit of my post was trying to understand why the 'closed' solution
provided in terms of hypergeometric function was not deemed suitable. The OP
already had an exact solution, but it seems that he is bothered with
functions whose evaluation might be time consuming.

Besides, in general an expression involving special functions will not lead
to an 'exact' number in that its evaluation could end up in an irrational
value, or in another expression whose value will have to be approximated.
What is the 'exact' value of sqrt(2) apart from its own expression?

>Moreover, sin and cos are NOT special functions.

I put 'special functions' in quotes. But since we are at it, I do not see
that much of a difference between a sin and bessel function, or a
sinintegral fucntion for what matters, from an operational point of view.
It's just a matter of were to find a routine to compute its values: either
built-in or imported. And computing the values is what matters to the OP.

cheers,
Peltio



.

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