Prove Sylow's 1st theorem

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General Idea:

Assuming Sylow's 2 Theorem Holds, Prove the 1st Sylow's Theorem.

Mathematically written:

if both are true:

  1. G is a finite Group

  2. Given such G, and prime number p, All Sylow p-subgroups are conjugate to each other

then G has a Sylow p-subgroup

My effort in trying to solve the problem:

  • I took the group $GL_n(\mathbb{F}_p)$ and showed it has a Sylow p-subgroup (denote $|A| = p^{\frac{|G|^2-|G|}{2}}$). (where $\mathbb{F}_p$ is the field of p elements)
  • Then I showed That a for any finite G, exist a bijective homeomorphism $\phi:G\rightarrow GL_{|G|}(\mathbb{F}_p)$
  • So if (hypothetically) G has a p-group $H\le G$ then $\phi (H) \subseteq GL_{|G|}(\mathbb{F}_p)$ is a p-subgroup as well.
  • Since $|G|=n=p^m*k$ for some k and a maximal m, And Since for any $m \le \frac{|G|^2-|G|}{2}$ exist a p-subgroup $B \le A$ with $|B|=p^m$.... there might be a way of showing that B(which exists!) is conjugated to a subgroup of $\phi(G)$
  • And By the bijectivity of $\phi$ we will conclude G has a Sylow p-subgroup.

I don't know how to complete the missing part, And would appreciate any help. thanks.