1) for a number say k > 1, raising to any power will increase its value.
eg. (2)2 = 4
but for any number say 0<k'<1 , raising to power will decrease its value.
Eg. (.2)2 = .04
This is the concept in the above thing.
2.) You're taking a = 1. So whatever Real power does a have, it's value will always remain 1.
Eg. 110000 = 1
And since by condition af(x)>b => 1>b.