1. The problem statement, all variables and given/known data Find a unit vector that is (a) parallel to and (b) normal to the graph of f(x) at the given point. Then sketch. f(x)=x^2 point=(3, 9) 2. Relevant equations None that I'm aware of. 3. The attempt at a solution Find parallel or perpendicular lines, planes, vectors, etc. to a given function has always been a problem for me. I never know where to start. Is it a matter of slope? If so, then how?