Hi,

You made a small error in plugging in 0 for k.

If you were to plug in 0, you would get

Now, probably is not defined on -1, so what you are trying to prove is this:

1. For , .

2. For , .

The second part can be proved by induction, proving the following two subparts seperately:

2a.

2b. If (induction hypothesis), then

Hope this helps