∫1+x−x−1ex+x−1dx is equal to
(x+1)ex+x−1+C
(x−1)ex+x−1+C
−xex+x−1+C
xex+x−1+C
∫1+x−x−1ex+x−1dx =∫xex+x−11−1x2+ex+x−1dx =xex+x−1−∫ex+x−1dx+∫ex+x−1dx =xex+x−1+C