Stuck at this induction problem

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I am giving it everything, but i just can't get it right.

The problem: Prove by induction that $n!>2^n$ for all integers $n\ge4$

I know how to solve the basic induction problems, but no matter what I do, I can't get this one right.

I saw how the problem is solved (schoolmate uploaded it on our class dropbox), but I just don't understand it.

The problem is, we only worked on the basics.

If someone could explain this like I'm five, that would be appreciated

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For $n=4$, we have that $4!=24>16=2^4$, so the condition holds. Now assume it's valid for $k\geq4$: $k!>2^k$. Then $$(k+1)!=(k+1)k!>(k+1)2^k>2\cdot2^k=2^{k+1},$$ and we hake that the condition holds for $k+1$.