I've got a HW problem I just cannot figure out. Can someone please explain how to solve this. I know it is a indeterminate limit and I was told to use algebraic laws to solve it, but my algebra is a little rusty.

Lim x->4 ( ( 1/sqrt(x)-2 ) - ( 4/x-4 ) ) ?

I know the answer is 1/4, but have no idea how that is the answer.

also,

Lim x->0 ( ( 3^(2x)-1 ) / ( 3^(x) -1 ) )

Thank you to anyone can help me with these two problems!