- #1
StrangeCharm
- 23
- 12
Homework Statement
∫ [x^(3)+4] / [x^(2)+4] dx
Homework Equations
N/A
The Attempt at a Solution
I know that the fraction is improper, so I used long division to rewrite it as x+(-4x+4)/[x^(2)+4].
Given the form S(x)+R(x)/Q(x), Q(x) is a distinct irreducible quadratic factor [x^(2)+4].
I used the rule ax^2+bx+c ⇒ (Ax+B)/(ax^2+bx+c) to rewrite it as (Ax+B)/[x^(2)+4].
I then solved for A and B and got A=-4 and B=4.
I am now trying to solve ∫ [ x + (-4x+4)/(x^(2)+4) ] dx
I know that ∫x=(1/2)x^2, but I am stuck with integrating (-4x+4)/[x^(2)+4].
(I tried u-substitution and that didn't work.)