The hard integral thread.

Original post by DFranklin

isn't that just for sequences?

.

Yes, but many of the sequences are decimal expansions of well known (and not so well known) numbers.

Reply 381

here is a detailed solution from an integral earlier

hopefully the extra detail helps some users

This website has a rather nice problem generator for many topics:
http://i-want-to-study-engineering.org/q/frightening_integral/

Reply 383

here is a detailed solution from another integral earlier

hopefully the extra detail helps some users

OP

Original post by TeeEm

here is a detailed solution from another integral earlier

hopefully the extra detail helps some users

After fiddling I got the the expansion part but that's is, really nice solution yet again TeeEm!

I haven't covered the Gamma function yet, it is similar to factorial right?

Could someone give me an integral which requires some series expansion, thanks! :biggrin:

(edited 8 years ago)

Reply 385

Original post by Louisb19

After fiddling I got the the expansion part but that's is, really nice solution yet again TeeEm!

I haven't covered the Gamma function yet, it is similar to factorial right?

gamma and beta are very nice and very easy
(they "do" it for me ...)

Learn the basics from a self teach book like advanced engineering mathematics by K Stroud
then go to my site and have practice

Reply 386

OP

Original post by TeeEm

gamma and beta are very nice and very easy
(they "do" it for me ...)

Learn the basics from a self teach book like advanced engineering mathematics by K Stroud
then go to my site and have practice

I remember seeing it when reading about the Riemann Hypothesis.

Why don't more teachers use your resources, 10x better than those damn Solomon worksheets!

Reply 387

username1162972

18

Original post by TeeEm

here is a detailed solution from another integral earlier

hopefully the extra detail helps some users

Remember this question, incredible question.

Posted from TSR Mobile

Reply 388

Original post by physicsmaths

Remember this question, incredible question.

Posted from TSR Mobile

a riddle of some sort?

Reply 389

username1162972

18

Original post by TeeEm

a riddle of some sort?

Lol no, forgot the 'I' at the start, the joys of doing lots of maths.

Posted from TSR Mobile

Reply 390

Zacken

22

Original post by Indeterminate

No takers? :sad:

Ok, allow me to do the honours.

PRSOM. Excellent. :-)

Reply 391

OP

\displaystyle\int_0^1 \dfrac{\mathrm{d} x}{\sqrt{1 - x^4}}

Very well may be impossible.

(edited 8 years ago)

Reply 392

Original post by Louisb19

\displaystyle\int \dfrac{\mathrm{d} x}{\sqrt{1 - x^4}}

I have not tried it but I do not think there is a closed form without limits

Reply 393

OP

Original post by TeeEm

I have not tried it but I do not think there is a closed form without limits

That is what I feared.

Reply 394

Kummer

7

Original post by Louisb19

That is what I feared.

If it's from 0 to 1 then the answer is:

Spoiler

Reply 395

OP

Original post by Kummer

If it's from 0 to 1 then the answer is:

Spoiler

That is what it was if I remember correctly. Could you post a solution?

Reply 396

Gregorius