3) Given the field extensions R c F C C, such that F contains all n'th roots of unity ξ = e2mk/n,...
fekri/n k0,1,...,n-1}, called the nth roots of unity. A primitive root of unity is = eri/n for which 2. The roots off(x) = x"-1 are the n complex numbers Cn and are ged(n, k) 1. It is easy to see that Q(C) is the splitting field of zn - 1. (a) For each n 3,... ,8, sketch the nth roots of unity in the complex plane. Use a different set of axes for each n. Next to each root, write...
Please answer A, B, and C in full 2. Let f() € F[2] be a separable polynomial with roots {u1, ..., Un} contained in some splitting field K of f(x) over F. Define A= || (ui-u) = (ui - U2) (u - u3) ...(ui-un)(uz - u3) ..(un-1 - Un) EK. (a) (15 points) Consider GalpK < Sn by looking at its action on the set of roots for f(x). Show that if Te Galo K is a transposition then (A)...
2. Discrete Fourier Transform.(/25) 1. N-th roots of unity are defined as solutions to the equation: w = 1. There are exactly N distinct N-th roots of unity. Let w be a primitive root of unity, for example w = exp(2 i/N). Show the following: N, if N divides m k=0 10, otherwise N -1 N wmk 2. Fix and integer N > 2. Let f = (f(0), ..., f(N − 1)) a vector (func- tion) f : [N] →...
Explain that with details thanks Topic: bilinear map and Tensor product (3) Let ơ (1, 2, ,n) E S,, be the cycle of length n. Let C, be the n x n matrix over an algebraically closed field k corresponding to σ, so Co (e) et+1 for i 1,..,n -1 and Ca(en)-e1. Show that and hence that C, is diagonalizible, similar to a diagonal matrix Dơ with diagonal entries 1,f, ξ2..-5n-1, where ξ is a primitive n-th root of unity...
6. (16 points) Let CE C be a primitive n-th root of unity. Let X = 6 + 1/5. (a) (4 points) Show that Q(5) R = Q(1). (b) (4 points) Let f be the minimal polynomial of over Q. Show that Q(x) is a splitting field of f over Q. (c) (4 points) Show that Gal(Q(^)/Q) – (Z/nZ)* / (-1). (d) (4 points) Find the minimal polynomial of 2 cos(27/9) over Q.
c. Let F : R³ → R³ be a vector field on R, given by the following function F(x, y, 2) = (x2)i + (y2)J + (xy)k. Calculate the flux of the field across the surface of the hemisphere, : [0, 1] × [0, 2x] → R³, where parametrized by the following function Þ(r, 0) = (r cos 0)i + (r sin 0) + (1 – 1²)!/2 k.
8. Let n be a positive integer. The n-th cyclotomic polynomial Ф,a(z) E Z[2] is defined recursively in the following way: 1. Ф1(x)-x-1. 2. If n > 1, then Фп(x)- , (where in the product in the denomina- tor, d runs through all divisors of n less than n). . A. Calculate Ф2(x), Ф4(x) and Ф8(z): . B. n(x) is the minimal polynomial for the primitive n-th root of unity over Q. Let f(x) = "8-1 E Q[a] and ω...
Prove the given definition, for parts a) through c). Lemma 9.3.5 (Orthogonality Lemma). Fir N and let w-wN-e2mi/N be the natural primitive Nth root of unity in C. Fort Z/(N), we have: N-1 ktN ift-0 (mod N), 0 otherwise. Lukt (9.3.5) k-0 9.3.2. (Proves Lemma 9.3.5) Fix N є N, and let w-e2m/N. Let f(x)-r"-1. o510 (a) Explain why N-1 (9.3.9) (Suggestion: Try writing out the sum as 1 +z+....) (b) Explain why for any t є z/(N), fw)-0. (c)...
Thee part question. Please answer all parts! Let E be a field of characteristic p > 0 (we proved p must always be prime). Verify that the ring homomorphism X : Z → E determined by sending χ : 1-1 E (the unity in E) ( so x(n)-n 1E wheren1E 1E 1E (n-times), x(-n)- nle for any n 1,2,3,... and X(0) 0E by definition of χ) is in fact a ring homomorphism with ker(X) = pZ. Úse the fundamental homomorphism...
Q3 (Prove that P∞ k=1 1/kr < ∞ if r > 1) . Let f : (0,∞) → R be a twice differentiable function with f ''(x) ≥ 0 for all x ∈ (0,∞). (a) Show that f '(k) ≤ f(k + 1) − f(k) ≤ f '(k + 1) for all k ∈ N. (b) Use (a), show that Xn−1 k=1 f '(k) ≤ f(n) − f(1) ≤ Xn k=2 f '(k). (c) Let r > 1. By finding...