The limit is , not
There are many ways to go about it.
Then you get:
The inside limit is a 'famous' one which equals -1/2, which easily derived using L'Hopital. You can do it without, but it's easier with the ol' Hospital rule
So, we have:
You wouldn't have to make the sub:
Start out with:
Now, use L'Hopital and get:
I hope you can read that. Sure is tiny. I have tried to make it bigger to no avail.