1. The problem statement, all variables and given/known data there is a surface xy3z2=4. What is the unit normal to this surface at a pt in the surface (-1,-1,2)?? 2. Relevant equations what is a unit normal to a scalar region? how can it be calculated? 3. The attempt at a solution i calculated the gradient (del operator) of this surface at the given point to be 3i-12j+4k . this is in the direction of the unit normal along which max. rate of increase occurs. So far so good. But how dowe get the unit normal from this ? i dont know how to go further.