Question

In: Advanced Math

Let X, Y ⊂ Z and x, y ∈ Z Let A = (X\{x}) ∪ {x}....

Let X, Y ⊂ Z and x, y ∈ Z Let A = (X\{x}) ∪ {x}.

a) Prove or disprove: A ⊆ X

b) Prove or disprove: X ⊆ A

c) Prove or disprove: P(X ∪ Y ) ⊆ P(X) ∪ P(Y ) ∪ P(X ∩ Y )

d) Prove or disprove: P(X) ∪ P(Y ) ∪ P(X ∩ Y ) ⊆ P(X ∪ Y )

Solutions

Expert Solution


Related Solutions

The curried version of let f (x,y,z) = (x,(y,z)) is let f (x,(y,z)) = (x,(y,z)) Just...
The curried version of let f (x,y,z) = (x,(y,z)) is let f (x,(y,z)) = (x,(y,z)) Just f (because f is already curried) let f x y z = (x,(y,z)) let f x y z = x (y z)
5. Let X, Y and Z be sets. Let f : X ! Y and g...
5. Let X, Y and Z be sets. Let f : X ! Y and g : Y ! Z functions. (a) (3 Pts.) Show that if g f is an injective function, then f is an injective function. (b) (2 Pts.) Find examples of sets X, Y and Z and functions f : X ! Y and g : Y ! Z such that g f is injective but g is not injective. (c) (3 Pts.) Show that if...
Let x, y ∈ Z. Prove that x ≡ y + 1 (mod 2) if and...
Let x, y ∈ Z. Prove that x ≡ y + 1 (mod 2) if and only if x ≡ y + 1 (mod 4) or x ≡ y + 3 (mod 4)
Let x, y, z be a primitive Pythagorean triple with y even. Prove that x+y ≡...
Let x, y, z be a primitive Pythagorean triple with y even. Prove that x+y ≡ x−y ≡ ±1 mod 8.
Let X and Y be independent and identical uniform distribution on [0, 1]. Let Z=min(X, Y)....
Let X and Y be independent and identical uniform distribution on [0, 1]. Let Z=min(X, Y). Find E[Y-Z]. Hint: condition on whether Y=Z or not. What is the probability Y=Z?
Let f(x,y) be a scalar function, and let F(x,y,z) be a vector field. Only one of...
Let f(x,y) be a scalar function, and let F(x,y,z) be a vector field. Only one of the following expressions is meaningful. Which one? a) grad f x div F b) div(curl(grad f)) c) div(div F) d) curl(div(grad f)) e) grad(curl F)
Let X and Y be independent positive random variables. Let Z=X/Y. In what follows, all occurrences...
Let X and Y be independent positive random variables. Let Z=X/Y. In what follows, all occurrences of x, y, z are assumed to be positive numbers. Suppose that X and Y are discrete, with known PMFs, pX and pY. Then, pZ|Y(z|y)=pX(?). What is the argument in the place of the question mark?    Suppose that X and Y are continuous, with known PDFs, fX and fY. Provide a formula, analogous to the one in part (a), for fZ|Y(z|y) in terms...
Given a function φ(z) with z = x+iy let    U(x, y) = ½ [φ(x+iy) +...
Given a function φ(z) with z = x+iy let    U(x, y) = ½ [φ(x+iy) + φ(x-iy)] and V(x, y) = i/2 [φ(x+iy) –φ(x-iy)] A) For φ(z) = z2 find U and V and their induced vector fields E =▼U and F =▼V also show that ▼2U = ▼2V = 0 B) Repeat for f(z) = z3 C) For f(z) = ln z we get U(x, y) = ½ ln (x2+y2) and V(x, y) = arctan (y/x) Find ▼U (electrostatic...
Prove Proposition 6.10 (Let f : X → Y and g : Y → Z be...
Prove Proposition 6.10 (Let f : X → Y and g : Y → Z be one to one and onto functions. Then g ◦ f : X → Z is one to one and onto; and (g ◦ f)−1 = f−1 ◦ g−1 ).
3. Let F : X → Y and G: Y → Z be functions. i. If...
3. Let F : X → Y and G: Y → Z be functions. i. If G ◦ F is injective, then F is injective. ii. If G ◦ F is surjective, then G is surjective. iii. If G ◦ F is constant, then F is constant or G is constant. iv. If F is constant or G is constant, then G ◦ F is constant.
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT