Homework Statement
Consider the set A={(u,v,w) in R^3 : u^2+v^2>0} and define a relation ~ on A by (u,v,w)~(u',v',w') IFF there exists a "k" in R, where k doesn't equal 0: (u',v',w')=(ku,kv,kw)
Prove that ~ is an equivalence relation of A
Homework Equations
I honestly don't know...