Answers

2016-02-04T14:44:37+05:30
If lt applies we get 0/0 but this is not exist 
so, apply LHospital rule
 Lt x -> 0   (a x e^ ax ) - (b x e^ bx)
                 ___________________________
                                1
now apply limit
you get,
          answer = a-b  (any power 0 is 1)
0