Problem 2. Suppose that A E Fand r and y are two elements of IFn. Prove...
Problem 2 Suppose two continuous random variables (X, Y) ~ f(x,y). (1) Prove E(X +Y) = E(X)+ E(Y). (2) Prove Var(X + Y) = Var(X) + Var(Y)2Cov(X, Y). (3) Prove Cov(X, Y) E(XY)- E(X)E(Y). (4) Prove that if X and Y are independent, i.e., f(x, y) Cov(X, Y) 0. Is the reverse true? (5) Prove Cov (aX b,cY + d) = acCov(X, Y). (6) Prove Cov(X, X) = Var(X) fx (x)fy(y) for any (x,y), then =
Let x, y, a, and b elements of the reals. Suppose |x - a| < e/(2(|b| + 1), |x - a| < 1, and |y - b| < e/(2(|a| + 1) for some e > 0. Prove that |xy - ab| < e.
5.7. Let n an E C be a multiplicative function defined by a 1 and ifn-2, pθ and 0 < θ < 1 . Prove that, as x → oo, we have where lEpl ano(a) for some constant r. 5.7. Let n an E C be a multiplicative function defined by a 1 and ifn-2, pθ and 0
Problem 2: For any x, y e R let d(x,y):-arctan(y) - arctan(x). Do the following: (1) Prove that d is a metric on R. (2) Letting xnn, prove that {xnJnE is a Cauchy sequence with no limit in R (Note that {xn)nen is NOT Cauchy under the Euclidean metric and that all Cauchy sequences in the Euclidean metric have a limit in R.) Problem 2: For any x, y e R let d(x,y):-arctan(y) - arctan(x). Do the following: (1) Prove...
Suppose that (a-r, a) C E or (a, a + r) C E, f : E → R, L E R, and (1) Prove that there exist numbers 0 < δ < r and M > 0 such that If(x)| < M for all (2) Prove that if L is nonzero, then there exist numbers 0 < δ < r and η > 0 such that limx→af(x) = L xEEwith 0 < |x-a| < δ. If(x)| > η for all...
Problem 4. Let n E N. We consider the vector space R” (a) Prove that for all X, Y CR”, if X IY then Span(X) 1 Span(Y). (b) Let X and Y be linearly independent subsets of R”. Prove that if X IY, then X UY is linearly independent. (C) Prove that every maximally pairwise orthogonal set of vectors in R” has n + 1 elements. Definition: Let V be a vector space and let U and W be subspaces...
Part 1 Part 2 7.1.2. Let R be a commutative ring and a, b E R, and define The goal of this problem is to prove that (a, b) is an ideal of R (a) Explain how you know that 0 E (a, b b) What do two random elements of (a, b) look like? Explain why their sum must be in (c) For s E R and z E (a,b), explain why sz E (a, b). 7.2.1. In the...
2) We define the relation R between two elements of S as: R= {(x,y) ifx is a subset of y or x-y) Show that R is a partial order.
Question 5. Let x,y E R. Prove that if x and y are irrational, then at least one of 2 + y and c-y is irrational
{(r, y) E R2 y r} Let A = {A,:r e R} be a collection of sets given by A, = Prove that A is a partition of R2 {(r, y) E R2 y r} Let A = {A,:r e R} be a collection of sets given by A, = Prove that A is a partition of R2