Integration using partial fractions?

ombudsmansect
Messages
29
Reaction score
0

Homework Statement



find the integral of (1 + 2x)/(1+x^2)

Homework Equations





The Attempt at a Solution



I honestly have no idea how to solve this and have spent ages trying to figure it out. I would automatically assume using partial fractions to solve but the denominator presents a problem there were it cannot take a form of a partial fraction. substitution does not work either. So if anyone has worked with a problem type like this before your advice would b greatly appreciated even a hint woud b awesome :)
 
Physics news on Phys.org
ombudsmansect said:

Homework Statement



find the integral of (1 + 2x)/(1+x^2)

Homework Equations





The Attempt at a Solution



I honestly have no idea how to solve this and have spent ages trying to figure it out. I would automatically assume using partial fractions to solve but the denominator presents a problem there were it cannot take a form of a partial fraction. substitution does not work either. So if anyone has worked with a problem type like this before your advice would b greatly appreciated even a hint woud b awesome :)

I seem to remember that if you have \frac{1+2x}{1+x^2}

That its possible split this up

thusly getting \frac{1}{1+x^2} + \frac{2x}{1+x^2}

That fact should be userable here :)
 
Last edited:
thanks suz! i will try n crack this thing now :D
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
Back
Top