Linear mapping? 3x3 matrices, give a geometric description of the map..?

How do I do this, what are the pictures like for:


a) ([-1,0,0],[0,-1,0],[0,0,1])


b) ([0,0,1],[1,0,0],[0,1,0])


c) 1/2([sqrt3,-1,0],[1,sqrt3,0],[0,0,2])


d)1/3([2,-1,-1],[-1,2,-1],[-1,-1,2])





Or explain what to do, please.