I don't know......
But good question......
I think...Maybe use binomial theorem...
If your'e trying to prove that a^k|b^k => a|b then
Now a|b iff n=m^k for some integer m, the problem is to show that it is so.
You can assume by contradiction that a!|b which means there exists p and r such that:
Now write a^k=(pb+r)^k and see that it contradicts our assumption.