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tangur
Nov16-04, 10:19 PM
Hi I need some help getting started with this integral

\int \frac {x^2+5x+2}{{x^4+x^2+1}}dx

Thanks in advance

Astronuc
Nov16-04, 10:55 PM
Try working the denominator -

x^4+x^2+1 = (x^4+2x^2+1)-x^2

then use the identity

x^2-y^2 = (x+y)(x-y)

Astronuc
Nov16-04, 11:41 PM
You were on the right track.

To eliminate the x^3 term, C=-A.

Then find 3 equations in three unknowns A, B, D.