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mathmajor2013
Feb24-11, 10:45 PM
Let p be a prime, k a pos. int., and G a group with |G|=p^k. Prove that G has an element of order p.

disregardthat
Feb24-11, 11:02 PM
Consider x^{\frac{m}{p}} for some element x not equal to the identity, where m is the order of x.

mathmajor2013
Feb24-11, 11:17 PM
This kind of seems like a contradiction because m/p is smaller than m, yet x^m/p=(x^m)^1/p=e^1/p=e.

disregardthat
Feb24-11, 11:20 PM
This kind of seems like a contradiction because m/p is smaller than m, yet x^m/p=(x^m)^1/p=e^1/p=e.

What does (x^m)^(1/p) mean?

mathmajor2013
Feb24-11, 11:25 PM
The pth root of x^m? I'm sorry I cannot see where this one is going

disregardthat
Feb24-11, 11:27 PM
The pth root of x^m? I'm sorry I cannot see where this one is going

You have written it yourself, but it doesn't make any sense. x^{\frac{m}{p}} makes perfect sense, since m divides p^k.