Hi, I've been working on these problems for hours and have failed every time, so I assume there's something fundamental I'm getting wrong either in applying L'Hospital's rule or in application of derivative laws.

Here's my first problem:

Lim as x->infinity of [16x/(16x+5)]^(9x)

The answer I got was e^(45/16) which is not correct.

I'll go over how I got what I got in a bit (have to catch a bus home).