Let u(x, y) = x^3 + kxy^2 + y. (a) Determine the value of k such...
Let u(x, y) = x^3 + kxy^2 + y. (a) Determine the value of k such
that u is an harmonic function. (b) Find the harmonic conjugate v
of u. (c) Obtain the expression of f = u + iv in terms of z = x +
iy
Let f ( x , y ) = x^ 2 + y ^3 + sin ( x ^2 + y ^3 ). Determine
the line integral of f ( x , y ) with respect to arc length over
the unit circle centered at the origin (0, 0).
Let f(x, y) = x^ 2 + kxy + 4y^ 2 , k a constant. The point (0,
0) is a stationary point of f. For what values of k will f have a
local minimum at (0, 0)?
(a) |k| > 4
(b) k ≥ −4
(c) k ≤ 4
(d) |k| < 4
(e) none of the above
The point P : (2, 2) is a stationary point of the function f(x,
y) = 6xy − x ^3...
Consider the series X∞ k=3 √ k/ (k − 1)^3/2 . (a) Determine
whether or not the series converges or diverges. Show all your
work! (b) Essay part. Which tests can be applied to determine the
convergence or divergence of the above series. For each test
explain in your own words why and how it can be applied, or why it
cannot be applied. (i) (2 points) Divergence Test (ii) Limit
Comparison test to X∞ k=2 1/k . (iii) Direct...
Let X and Y have the following joint density function
f(x,y)=k(1-y) , 0≤x≤y≤1.
Find the value of k that makes this a probability density
function.
Compute the probability that P(X≤3/4, Y≥1/2).
Find E(X).
Find E(X|Y=y).
Let u(x, y) be the harmonic function in the unit disk with the
boundary values u(x, y) = x^2 on {x^2 + y^2 = 1}. Find its
Rayleigh–Ritz approximation of the form x^2 +C1*(1−x^2
−y^2).
Let X and Y have joint pdf f(x,y)=k(x+y), for 0<=x<=1 and
0<=y<=1.
a) Find k.
b) Find the joint cumulative density function of (X,Y)
c) Find the marginal pdf of X and Y.
d) Find Pr[Y<X2] and Pr[X+Y>0.5]
a) U = xy b) U = (xy)^1/3 c) U = min(x,y/2) d) U = 2x + 3y e) U
= x^2 y^2 + xy
4. All functions except c) are differentiable. Do these
functions exhibit diminishing marginal utility? Are their
Marshallian demands downward sloping? What can you infer about the
necessity of diminishing marginal utility for downward- sloping
demands?