I need help with a, b, and c. 7.Let A be ann x n real symmetric invertible matrix, let B Rt and C E R. Define f:R R by 2 a. Give f (a) c. Give f"(x) d. Prove that if A is positive definite and u is the critical point of f, then f(u) < f(x) for all x E Rn where x Prove that if A is negative definite and u is the critical point of f, then...
a through e is considered one question. 7.Let A be ann x n real symmetric invertible matrix, let B Rt and C E R. Define f:R R by 2 a. Give f (a) c. Give f"(x) d. Prove that if A is positive definite and u is the critical point of f, then f(u) < f(x) for all x E Rn where x Prove that if A is negative definite and u is the critical point of f, then f(u)...
1) Let f:R-->R be defined by f(x) = |x+2|. Prove or Disprove: f is differentiable at -2 f is differentiable at 1 2) Prove the product rule. Hint: Use f(x)g(x)− f(c)g(c) = f(x)g(x)−g(c))+f(x)− f(c))g(c). 3) Prove the quotient rule. Hint: You can do this directly, but it may be easier to find the derivative of 1/x and then use the chain rule and the product rule. 4) For n∈Z, prove that xn is differentiable and find the derivative, unless, of course, n...
Let A be n × n with AT-A. (The matrix A is syrnmetric.) Let B be 1 × n and let c E R. Define f : Rn → R by f(x) = 2.7, A . x + B . x + c. Show that The function f is a quadratic function Let A be n × n with AT-A. (The matrix A is syrnmetric.) Let B be 1 × n and let c E R. Define f : Rn...
Exercise 7.9. Assume f:R → R. (a) Let t € (1,0). Prove that if |f(x) = alt for all x, then f is differentiable at 0. (b) Let t € (0,1). Prove that if f(x) = |x|* for all x, and f(0) = 0, then f is not differentiable at 0. (c) Give a pair of examples showing that if |f(x)= |x|for all I, then either conclusion is possible.
(6) Let fel ), where is Lebesgue measure on R. Define F:R → R by F(x) = f' f(t) dx. (a) Prove that F is a continuous function. (b) Prove that F is uniformly continuous on R. (Note that R is not compact.)
5. Define f:R + R by f(x) = x2 if x is rational, and f(x) = 0 if x is irrational. Show that f'(0) exists and is equal to zero.
7. Consider the function f:R + R defined by f(x) = x < 0, 3 > 0. e-1/x2, Prove that f is differentiable of all orders and that f(n)(0) = 0 for all n e N. Conclude that f does not have a convergent power series expansion En Anx" for x near the origin. [We will see later in this class that this is impossible for holomorphic functions, namely being (complex) differentiable implies that there is always a convergent power...
(1) (Definition and short answer — no justification needed) (a) Let f:R → R", and let p ER". Define carefully what it means for the function f to be differentiable at p. (b) Given a linear transformation T : R" + R", explain briefly how to form its representing matrix (T). If you know the matrix (T), how can you compute T(v) for a vector v € R"? 1 and let S be the linear (c) Let T be the...
5. Define f:R → R by f(x) = ax + b where b = 0 Is f a linear transformation? Justify your answer.