so i see this form is infinity infinity and i need to convert it to some type of quotient form to use lhospitals rule, but don't really understand it conceptually.

so for example LIM(x->infi) (x - lnx)

i rewrite as

LIM(x->infi) X(1 - lnx/x) <-- now have indeterminate type infi/infi

but now i dont understand why the hospital rule is only applied to the lnx/x. are we saying compared to how large or negative lnx/x will be in the function that the 1 is dismissable? or does it have something to do with the factored x? :S


edit: nvm got it i think.. apply hospital rule to lnx to force 1/1/x, 1-1=0 * x=0 which is your limit

This post was edited by CrackerJacker on Jul 22 2014 10:43pm

iirc that rule just differentiates the top and bottom of a fraction. derivative of a constant is 0.