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View Full Version : Looking for table of primitives


quasar987
Oct5-04, 08:40 AM
Hi, I'm looking for an ONLINE table of primitives. Does anybody know of a good website?

Thanks

quasar987
Oct5-04, 09:39 AM
Or for now, does anybody know what this integral is


\int \frac{sinx}{\sqrt{1 + 3sin^2x}}dx


?

Zurtex
Oct5-04, 10:04 AM
Let u = cos(x)

quasar987
Oct5-04, 10:43 AM
?!

That's not it. We're still stuck with the square root.

Muzza
Oct5-04, 11:06 AM
It is indeed "it".

If u = cos(x), then u^2 = cos^2(x) = 1 - sin^2(x) (etc)... The "new" integral can be handled with an inverse trigonometric function.

quasar987
Oct5-04, 11:13 AM
That's genius! Thanks both of you!

I'm still interested in a table of primitive though ;)