1/(a+1)<ln((1+a)/a)<1/a

Questions
1

For a>0, prove that:

1/(a+1)<ln((1+a)/a)<1/a

2 
Simplify[
 Reduce[1/(a + 1) < Log@((1 + a)/a) < 1/a, a, Reals],
 a > 0
 ]