Consider the set U of 2 X 2 matrices where all the elements are nonnegative. Is U a vector space?

L24 - 9 Now You Try It (NYTI): 2/3 1. Let f(x)= x − 2. Show that f(−1) = f(1) but there is no value of c in (−1,1) so that f (c) = 0. Why does that not contradict Rolle’s Theorem 2. If f(2) = −2a d f (x) ≥− 1f r x in [2,5], how small can f(5) possibly be 3. Suppose that f(x) is an odd function which is diﬀerentiable on (−∞,∞). ▯ f(a) Show that if a> 0, there is some x in (−a,a)s otat f (x)= a .