Kindly solve these questions

Exercise 2. Let f: R" -+ R be a real-valued function on R", and X0 = ER" a In point. (a) If f is differentiable at Xo, explain what it means to say that the function z = h(x), where h(x) = f(Xo) + Df(xo) (x -Xo) is the best linear function to approximate f at Xo. (b) Suppose f is differentiable at the point x = X1, and Df (x,) = [0 .. o]. the 0-matrix. Describe what may be happening to graph(f) at or near X Xp. (c) Suppose f is not differentiable at x = x2. At this point, all of the partial derivatives exist and are continuous as functions, except for one: In the ith coordinate direction, we found of f ( xz tell ) - /(x.) (x2) = lim Describe what may be happening to graph ( flat or bear X Xy2. (a) Define, and carefully explain in your own words, what it means for a function f : R - R to be differentiable at a point Xo E R. (b) Plot the function f : R - R in a graph, where f (x ) = |x - 1| ifxs 2. aX- if x > 2. (Recall (z) = z if z 2 0 and |z| = -z if z