The limit of as the basis of the next operation, and then take the limit; ② As long as there is no infinitive in the following forms after replacement:
0/0; ∞/∞; 1^∞; ∞^0; ∞-∞; 0^0; 0? ∞; When you encounter these infinitives, you need to do some processing before you can substitute them.
If it is 0/0 or ∞ /∞, it can be handled by L'H?pital's law.
In your operation, because ln 1=0, you will have 0/0 after you substitute it. Please note that all x's on the numerator denominator should be replaced by 0.
It is infinitive, which means it can't be replaced yet.