The unit vector I obtain is , the gradient is so the dot product is the function , at the point you're given I'm obtaining
Im studying for a final and I just need some reassurance.
1. Find the directional derivative of
I found partial derivatives, found the direction vector, found the unit vector, My answer is
2.Find the area of the surface over the region
I setup double integral using polar coordinates, r from 0 to 4, theta from 0 to 2pi.
My final answer is 256pi/3.