Suppose that the maximum rate of change of f at (1,-1) is 10, and it occurs in the direction of 3vec(i)-3vec(j). Find gradf(1,-1), f_(x)(1,-1), and f_(y)(1,-1).
A) What is the maximum rate of change of f at (1,-1)?
B) In which direction does the maximum rate of change occur at (1,-1)?
C) Calculate gradf(1,-1).
D) Calculate f_(x)(1,-1) and f_(y)(1,-1).
