Math question: Integrals

[Sirotnikov]

i know it's probably dead simple so don't laugh

i need to perform an integral on (sqrt(x))/(x^2+3)
but idon't know how

it's a complex function and i'm not sure how to do the 1/(x^2+3) ... i know it's supposed to be some form of ln(x)... but i just don't know

help...

[BlackCat]

It's probably cheating but try :

http://integrals.wolfram.com/index.jsp

[Kuciwalker]

Feel free to use any computer algebra system. Integration is solved problem.

[Sirotnikov]

i was kinda hoping for an explanation, cause i need to know how to solve it manually.

[Whoha]

substitution, partials,who knows. I'd have to look in a book.

[Ramo]

i was kinda hoping for an explanation, cause i need to know how to solve it manually.

The explanation is in the solution. Differentiate the solution, and work backwards. Basically, you add a bunch of zeros (i.e +f(x)-f(x)), and you should end up with some ln's and arctan's.

[Sirotnikov]

lans and arctans?
that's disgusting *ugh*

[Sirotnikov]

i hate trigonometry derivatives.
they totally suck donkey ass

[Ramo]

I assume you're having problems with arctan? It's pretty easy. Just use the composition rule. For instance:

d/dx (tan o arctan(x))= d/dx x = 1

Thus,

(d/dx arctan(x))(d/dx' tan(x'=arctan(x)))=1

Therefore:

d/dx arctan(x) = 1/(1+x^2)

[Sirotnikov]

stuff like that yes

and integrals crap like sin²(x) which apparently should be changed to simpler terms, because it is damn near impossible to integrate

[TheStinger]

the answer is 7