Assignment:
Let f(x,y) be an infinitely differentiable function. Suppose that
a. f(0,0) = 0
b. f_x(0,0) = 0 and f_y(0,0) = 0.
Consider the surface z = f(x,y). Show that K(0,0) = f_xx(0,0) f_yy(0,0) - f_xy(0,0)^2.
Provide complete and step by step solution for the question and show calculations and use formulas.