g(a,b,c)=(a^x)+(b^y)+(c^z)+x(a)+y(b)+z(c)
If variables a,b,c are greater than 0, and variables x,y,z are values between 0 and 1, is this function convex, strictly convex, concave, strictly concave, or none of the stated options?
g(a,b,c)=(a^x)+(b^y)+(c^z)+x(a)+y(b)+z(c) If variables a,b,c are greater than 0, and variables x,y,z are values between 0 and...
Problem 4. (15 points each) Let F(x, y, z) = (0, x, y) G(x, y, z) = (2x, z, y) + (x, y, z) = (3y, 2x, z). (a) For each field, either find a scalar potential function or prove that none exists. (b) For each field, either find a vector potential function or prove that none exists. (c) Let F(t) = (2, 2t, t2). For which of these vector fields is ñ a flow line? Justify your answer.
You are given three independent random variables: X, Y, and Z. The expected values of each are 0, and the variances of each are 1. Let U1 =Y + Z and let U2 = X – Y. (a) What are the variances of U1 and U2? (b) What is Cov(U1, U2)? (c) Combining your answers to (a) and (b), what is the correlation coefficient p between U1 and U2?
The joint probability density function of the random variables X, Y, and Z is (e-(x+y+z) f(x, y, z) 0 < x, 0 < y, 0 <z elsewhere (a) (3 pts) Verify that the joint density function is a valid density function. (b) (3 pts) Find the joint marginal density function of X and Y alone (by integrating over 2). (C) (4 pts) Find the marginal density functions for X and Y. (d) (3 pts) What are P(1 < X <...
14. If y =f(z) is a continuous function in a neighborhood around f'(c) = 0, does there have to be a local extrema on the graph of u = f(x) at x = c. 15. If/"(z) =-4(-7)2(z + 1) and the domain of f(x) is all real numbers, determine where f(x) is concave up, concave down and find any r-values of inflection points. 14. If y =f(z) is a continuous function in a neighborhood around f'(c) = 0, does there...
Suppose X, Y and Z are three different random variables. Let X obey Bernoulli Distribution. The probability distribution function is p(x) = Let Y obeys the standard Normal (Gaussian) distribution, which can be written as Y ∼ N(0, 1). X and Y are independent. Meanwhile, let Z = XY . (a) What is the Expectation (mean value) of X? (b) Are Y and Z independent? (Just clarify, do not need to prove) (c) Show that Z is also a standard...
5. Random variables X U[0, 1 and Y ~Exp(1) are independent (a) Compute P(X Y > z) for the case 0 S1 and the case z >1. b) Compute and plot the pdf of XY. (c) Give the MGF of X Y. 5. Random variables X U[0, 1 and Y ~Exp(1) are independent (a) Compute P(X Y > z) for the case 0 S1 and the case z >1. b) Compute and plot the pdf of XY. (c) Give the...
Implicit Function Theorem in Two Variables: Let g: R2 → R be a smooth function. Set {(z, y) E R2 | g(z, y) = 0} S Suppose g(a, b)-0 so that (a, b) E S and dg(a, b)メO. Then there exists an open neighborhood of (a, b) say V such that SnV is the image of a smooth parameterized curve. (1) Verify the implicit function theorem using the two examples above. 2) Since dg(a,b) 0, argue that it suffices to...
1. Suppose that X and Y are random variables that can only take values in the intervals 0 X 2 and 0 Y 3 2. Suppose also that the joint cumulative distribution function (cdf) of X and Y, for 0 < 2 and 03 y 3 2, is as follows: Fy). 16 [5] (a) Determine the marginal cdf Fx(x) of X and the marginal cdf Fy () of Y [5] (b) Determine the joint probability density function (pdf) f(x, y)...
using discrete structures 3. Consider the function F(x, y, z) for x, y, z z 0 defined as follows: a. F(x, y, 0)-y+1 b. F(x, 0, 1)-x c, F(x, 0, 2) = 0 d. F(x, 0, z+ 3)-1 e. F(x, y, z)-F(x, F(x, y-1, z), z-1) Using Induction, prove the following a. F(x, y, 1)-x +y b, F(x, y, 2) = xy c. F(x, y, 3)-xy 3. Consider the function F(x, y, z) for x, y, z z 0 defined...
5. Let X, Y, Z be random variables with joint density (discrete or continuous) plr, y,a) a f(x, 2)g(y, 2)h() Show that (a) p(rly, s) x /(r, :), ie. P(rly, :) is a function of 1 and :; (b) p(y|z, z) g(y, z), İ.e. p(y|z,z) is a function of y and z; (c) X and Y are conditionally independent given Z