am try to integrat the following
 

int((z-x)f(x), x=L...z-1)
 

where f(x) is an undefined PDF, L is the lower bound H is the upper
bound.  The results should look like this
 

(z-1)F(z-1)+int(F(x), x=L..(z-1))  using integration by parts
 

Similarly  I want to integrat
 

int(xf(x), x=z..H) again, using integration by parts the result I am
lookig for should be
 

xF(x) - int(1-F(x), x=z..H).