How do you integrate (2x^3-3x^2+x+1)/(-2x+1)2x33x2+x+12x+1?

1 Answer
Sep 14, 2015

-x^3/3+x^2/2-1/2lnabs(2x-1)+Cx33+x2212ln|2x1|+C

Explanation:

We have to divide polinomials:

(2x^3-3x^2+x+1):(-2x+1)=-x^2+x(2x33x2+x+1):(2x+1)=x2+x
-2x^3+x^22x3+x2
----
-2x^2+x+12x2+x+1
+2x^2-x+2x2x
----
11

(2x^3-3x^2+x+1)/(-2x+1)=-x^2+x+1/(-2x+1)2x33x2+x+12x+1=x2+x+12x+1
int(2x^3-3x^2+x+1)/(-2x+1)dx=2x33x2+x+12x+1dx=
=int(-x^2+x+1/(-2x+1))dx==(x2+x+12x+1)dx=
=-intx^2dx+intxdx-intdx/(2x-1)=I=x2dx+xdxdx2x1=I
2x-1=t, 2dx=dt, dx=dt/22x1=t,2dx=dt,dx=dt2
I=-x^3/3+x^2/2-intdt/2 1/t= I=x33+x22dt21t=
=-x^3/3+x^2/2-1/2lnabs(2x-1)+C=x33+x2212ln|2x1|+C