# Solving Problems From The Back - 6

In order for us to apply Fermat's Little Theorem, we need $$p \neq 2$$.

Breadcrumb 7: If $$p = 2$$, then $$2 \mid f(2^n)$$. We need another approach here.
Exercise 10: Deal with this yourself.

Now that I've walked you through how to figure out this proof from the end result, write out the proof as you would present it.

Exercise 11: Write out a complete proof to the original question.

Ponder this, and you are done.

Note by Calvin Lin
4 years, 2 months ago

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