# Looking for table of primitives

1. Oct 5, 2004

### quasar987

Hi, I'm looking for an ONLINE table of primitives. Does anybody know of a good website?

Thanks

2. Oct 5, 2004

### quasar987

Or for now, does anybody know what this integral is

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

?

3. Oct 5, 2004

### Zurtex

Let u = cos(x)

4. Oct 5, 2004

### quasar987

?!

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

Last edited: Oct 5, 2004
5. Oct 5, 2004

### Muzza

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.

6. Oct 5, 2004

### quasar987

That's genius! Thanks both of you!

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