I think we need an additional assumption that ; otherwise the claim is not true.
So assuming , as a first step let's see if we can show that if and then .
We have
so
, hence .
Finally, to show that if and then , let above.
I think we need an additional assumption that ; otherwise the claim is not true.
So assuming , as a first step let's see if we can show that if and then .
We have
so
, hence .
Finally, to show that if and then , let above.