1) Define the statement that you'll prove by induction holds for every n:

2) Show Statement(1) is true.

3) ASSUME Statement(k) is true for some k >=1. From that algebracially manipulate it so that you can show that Statment(k+1) must also be true.

It should look like this:

4) 1-3 completes the proof by induction:

You've shown Statement(1) is true by #2,

and, by #3, you've shown thatStatement(k) is true,ifStatement(k+1) is true.then

Therefore, you've proven Statement(n) is true for all n>=1.