First I want to say hello to everyone in here. I'm a noob. Here is my problem. Let u=(1.2.0), v=(0,0,3), and w=(0,1,0) are vectors in R^3. Evaluate, if defined, the following expretions (if undefined state so) a) (u * v)w b) u+w*v c) (u * u)/w d) (v * v)/(w * w) Should I try to calculate them or just tell if expretion is defined or undefined? How can I tell if expretions above are defined?