Proving Non-Linearity of a Transformation in R^3

[Rounder01]

Okay, I will just admit that I stink at using mathematical proof in Linear. I hope someone can give me a push with this problem

Prove that T : R(real)^3 -> R(real)^3 defined by T([yz,xz,zy]) is not a linear transformation.

Reading my book I know that I need to prove that the transformation is closed under additivity and scalar multiplication, but alas I do not know where to begin with this. Any help would be appreciated.

 

[CrusaderSean]

I never did any proofs in linear algebra, but I think you can prove it by showing counter example.
linear transformation means T(v+w) = T(v) + T(w) where v,w are vectors in R^3
take v=[1 0 0] and w=[0 0 1] and see what you can when you apply transformation.