Proof of Abelian Property of G Showing

[Punkyc7]

Thanks I figured it out.

 

[Poopsilon]

Start with the identity (gh)^5 = g^5h^5, do what you can with inverses, then go to (gh)^3 = g^3h^3 and do the same, then see if you can make a substitution back into the first one, from here just see what's equal to what and play around for a bit with inverses, I didn't even need to use (gh)^4 = g^4h^4.