Exercise 12.3.4. Let x, y,2, w be variables. Prove that ry - zw, the determinant of...
Exercise 2 (pts 5). Let g() E Z[2]. Prove that g(x) is irreducible over Zx if and only if g() is irreducible as polynomial in Q[o].
Let z and w be non-zero complex numbers such that zw /=1. Prove that if z= z^(-1) and w=w^(-1),then (z + w)/(1+ zw) is real.I know z * z^(-1) = 1.
Number Theory
13 and 14 please!
13)) Let n E N, and let ā, x, y E Zn. Prove that if ā + x = ā + y, then x-y. 14. In this exercise, you will prove that the additive inverse of any element of Z, is unique. (In fact, this is true not only in Z, but in any ring, as we prove in the Appendix on the Student Companion Website.) Let n E N, and let aE Z...
Let k be a field of positive characteristic p, and let f(x)be an irreducible polynomial. Prove that there exist an integer d and a separable irreducible polynomial fsep (2) such that f(0) = fsep (2P). The number p is called the inseparable degree of f(c). If f(1) is the minimal polynomial of an algebraic element a, the inseparable degree of a is defined to be the inseparable degree of f(1). Prove that a is inseparable if and only if its...
Exercise 11. Let Xi,Y be random variables with joint PDF fxi.Y. Let X2,Y be random variables with joint PDF fXyXy Let T: R2 → R2 and let S: R2 → R2 so that ST(x,y) = (z, y) and TS(z, y)-(x,y) for every (x,y) є R2. Let J(z, y) denote the determinant of the Jacobian of S at (x,y). Assume that (X2,Y) = T(X1Ύǐ). Using the change of variables formula from multivariable calculus, show that fx2 x2 (x, y)-fx .yi (S(x,...
Exercise 11. Let Xi,y, be random variables with joint PDF fXiXi. Let X2,Y2 be random variables with joint PDF fx2,Y2. Let T: R2R2 and let S: R2 -R2 so that ST(x, y) (z, y) and TS(a, y) (x, y) for every (x, y) E R2. Let J(x, y) denote the determinant of the Jacobian of S at (x,y. Using the change of variables formula from multivariable calculus, show that
The random variables X and Y are independent with exponential densities fx (x) = e-"u(x) (a) Let Z = 2X + and w =-. Find the joint density of random variables Z and W (b) Find the density of random variable W (c) Find the density of random variable Z
The random variables X and Y are independent with exponential densities fx (x) = e-"u(x) (a) Let Z = 2X + and w =-. Find the joint density of random...
Exercise 6.15. Let Z, W be independent standard normal random variables and-1 < ρ < l. Check that if X-Z and Y-p2+ VI-p-W then the pair (X, Y) has standard bivariate normal distribution with parameter ρ. Hint. You can use Fact 6.41 or arrange the calculation so that a change of variable in the inner integral of a double integral leads to the right density function.
3. (Bpoints) Let X, Y and Z be independent uniform random variables on the interval (0, 2), Let W min(X, y.z a) Find pdf of W Find E(1-11 b)
3. (Bpoints) Let X, Y and Z be independent uniform random variables on the interval (0, 2), Let W min(X, y.z a) Find pdf of W Find E(1-11 b)
2. Let X and Y be two continuous random variables varying in accordance with the joint density function, fx.y(z, y-e(x + y) for 0 < z < y < 1. Solve the following problem s. (1) Find e, fx(a) and fy (v) (2) Find fx-u(z) and fY1Xux(y) (8) Find P(Y e (1/2, 1)|X -1/3) and P(Y e (1/2,2)| X 1/3). 3. Find P(X < 2Y) if fx.y(zw) = x + U for X and Y each defined over the unit...