Indefinite Integration

If \(I=\int \frac{e^x}{e^{4 x}+e^{2 x}+1} d x\) and
\(J=\int \frac{e^{-x}}{e^{-4 x}+e^{-2 x}+1} d x\), then for any arbitrary constant \(C\), than the value of \(J-I\) equals