Recent content by jbarbarez

Consider the following functions each of which is defined on the x - y plane f1(x) = (x-y)/(x+y) if x + y is not 0 and otherwise f1(x,y) = 0 f2(x,y) = (xy)/(x^2 + y^2) if (x,y) is not (0,0) and otherwise f2(0,0) = 0 f3(x,y) = (x^3 - y^3)/(x^2 + y^2) if (x,y) is not (0,0), and otherwise...