By definition:

such that whenever then it follows that

In these questions, you always fudge the last expression to get in terms of in which you set to. So:

So the problem is the . To deal with this, we can assume that we're dealing with relatively small values so we can say (Normally we use but we run into a bit of a problem so we choose a different value). So:

Adding +1 to all 3 sides we get:

Can you finish off?