Polynomials Definition and 784 Threads

  1. C

    Four proof that exercises about taylor polynomials

    Four "proof that" exercises about taylor polynomials Homework Statement Definition: A function f is called C^n if f n times derivable and if the n-time derivable f^(n) is continuos. If is from class C^n then its called f ε C^n Exercise 1) Be f ε C^n in the interval [a,x]. Be P a polynomial...
  2. T

    Why Does the Polynomial Remainder Theorem Yield All Real Numbers for b?

    Homework Statement When 3x5 - ax + b is divided by x - 1 and x + 1 the remainders are equal. Given that a, b ε ℝ (a) the value of a; (b) the set of values of b. Homework Equations The Attempt at a Solution f(1) = f(-1) 3 - a + b = -3 + a + b 6 = 2a a = 3 ... [1] Substitute a -3 into 3 - a +...
  3. facenian

    Question about Orthogonal Polynomials

    Hello, I'm studing the hydrogen atom and I found an unified presentation of orhtogonal polynomials in the book by Fuller and Byron. I would like to learn more about it but in the same spirit(for physicits not for mathematicians). Can someone give some references where to find more?
  4. J

    Write the polynomials in x as polynomials of

    The problem statement Write the following polynomials in x as polynomials of (x-3) Solution should be somewhat analytical in its approach. How would you do something like this? What does it mean? You can use any example to explain it, my specific homework question isn't necessary unless you...
  5. fluidistic

    Legendre polynomials, Jackson's book problem, potential

    Homework Statement I'm stuck in evaluating an integral in a problem. The problem can be found in Jackson's book page 135 problem 3.1 in the third edition. As I'm not sure I didn't make a mistake either, I'm asking help here. Two concentric spheres have radii a,b (b>a) and each is divided into...
  6. R

    MHB Find polynomials in S, then find basis for ideal (S)

    Hi There, I posted this question over at MHF to no avail, I'm not really sure what the ruling is on this kind of thing, I know this site was setup when MHF was down for a long time but you seem to still be active and a lot of clever people are still here so hopefully you don't mind taking a...
  7. J

    Derivation for Rodrigues formula (orthogonal polynomials)

    Okay, so given a family of orthogonal polynomials under a weight w(x) is described by the differential equation Q(x) f'' + L(x) f' + \lambda f = 0, where Q(x) is a quadratic (at most) and L(x) is linear (at most). with the inner product \langle f | g \rangle \equiv \int_X f^*(x) g(x)...
  8. K

    Show that two polynomials cannot span P2.

    Hi I know the dimension is 3, two polynomials has dimension 2 only so it cannot span P2. How would I go about showing it if I were to write it down mathematically? Thanks
  9. S

    Multiplying polynomials in Mathematica

    I have two polynomials (1+x+x^2+x^3) and (1+x+x^2+x^3+x^4), I'm trying to figure out how to compute the product in Mathematica, but it's not working. Any help is appreciated, thanks.
  10. R

    Abstract algebra: monic gcd of polynomials in a subfield problem

    Homework Statement Let K \subseteq L be fields. Let f, g \in K[x] and h a gcd of f and g in L[x]. To show: if h is monic then h \in K[x]. The Attempt at a Solution Assume h is monic. Know that: h = xf + yg for some x, y \in K[x]. So the ideal generated by h, (h) in L[x] equals...
  11. D

    Alternate Expression (Interpolation with Polynomials)

    Difficulty : College Homework Statement The Attempt at a Solution I am unsure how to approach this question. I think it involves a process where you add an expression & and subtract it (or multiply & divide) in order to manipulate the equation and rearrange it or reorder it. I've...
  12. L

    A problem while verifying the generating function of Legendre Polynomials.

    Our professor gave us an a problem to solve, she asked us to prove or verify the following identity: http://img818.imageshack.us/img818/5082/6254.png Where \Phi is the Generating function of Legendre polynomials given by: \Phi(x,h)= (1 - 2hx + h2)-1/2 2. This Identity is from...
  13. A

    MHB Proving Orthogonal Polynomials: A Weighted Integral

    Let \{ \phi_0,\phi_1,...,\phi_n\} othogonal set of polynomials on [a,b] n>0, with a weight function w(x) prove that \int_{a}^b w(x)\phi_n Q_k (x) \; dx = 0 for any polynomail Q_k(x) of degree k<n ? My work : I think there is a problem in the question since if we take x^2,x^3 on the...
  14. A

    An integral over three Legendre polynomials

    Homework Statement I encountered the following integral in my research, and I've yet to find an analytic solution: I(n_1,n_2,n_3) = \int_{-1}^{1} d(\cos\theta_1) \int_{-1}^{1} d(\cos\theta_2) P_{n_1}(\cos\theta_1) P_{n_2}[\cos(\theta_1-\theta_2)] P_{n_3}(\cos\theta_2) where P_n(x) is the nth...
  15. J

    Is \( u^p \) a root of \( f(x) \) over \( GF(p) \) if \( u \) is a root?

    If F is a field of characteristic p, with prime subfield K = GF(p) and u in F is a root of f(x) (over K), then u^p is a root of f(x). Now, I know that x^p \equiv x (\text{mod } p), so isn't it immediately true that f(x^p)=f(x) (over K)? So, 0=f(u)=f(u^p) . I only ask because this type...
  16. E

    Error estimate for Taylor polynomials

    Use the error estimate for Taylor polynomials to find an n such that | e - (1 + (1/1!) + (1/2!) + (1/3!) + ... + (1/n!) | < 0.000005 all i have right now is the individual components... f(x) = ex Tn (x) = 1/ (n-1)! k/(n-1)! |x-a|n+1 = 0.000005 a = 0 x = 1 I don't know where to go from here
  17. J

    Mathematica [Mathematica] Formatting output of polynomials

    Hi guys, I seem to still be having problems formatting polynomials in a standard way in Mathematica. I generate them randomly and would like them output using Print in a particular format. Say I have: theFunction=-2 + w^3 (-9 - 3 z) - 7 z + w^2 (4 + 5 z) + w (8 - 2 z^2) + w^4 (-5 z^2...
  18. H

    Solving Polynomial Equations with Exponents of 40

    Polynomials help~~ Heh, so I posted this thread in the wrong category so I'm reposting it! =) Hello. So here was this problem I came across: If x^4-x^3+x^2-x^1+x^0=0, what is the numerical value of x^40-x^30+x^20-x^10+x^0? I did try doing many stuffs (symmetry) & factoring, but I think...
  19. M

    Explicitly describing the singular locus from a finite set of polynomials

    When explicitly given a set of polynomial equations, I am interested in describing its singular locus. I read this from several sources that a point is singular if the rank of a Jacobian at a singular point must be any number less than its maximal possible number. Or is it the locus where all...
  20. J

    What is the Proof for the Relation Between Legendre Polynomials and Sums?

    Following relation seems to hold: \int^{1}_{-1}\left(\sum \frac{b_{j}}{\sqrt{1-μ^{2}}} \frac{∂P_{j}(μ)}{∂μ}\right)^{2} dμ = 2\sum \frac{j(j+1)}{2j+1} b^{2}_{j} the sums are for j=0 to N and P_{j}(μ) is a Legendre polynomial. I have tested this empirically and it seems correct. Anyway, I...
  21. S

    Proof by Contradiction: Irreducible Polynomials and Ideals

    Homework Statement (see attachment) Homework Equations The Attempt at a Solution I have been attempting a proof by contradiction (for the last statement) for a while now, but I can't seem to reach a contradiction from these premises: 1 ≤ deg(f) ≤ deg(g) (without loss) N ≠...
  22. T

    Integrals of products of Hermite polynomials

    Hey people, I need to calculate inner product of two Harmonic oscillator eigenstates with different mass. Does anybody know where I could find a formula for \int{ H_n(x) H_m(\alpha x) dx} where H_n, H_m are Hermite polynomials?
  23. C

    Can Polynomials with Integer Coefficients be Counted using Prime Numbers?

    Homework Statement Let A_n be the algebraic numbers obtained as roots of polynomials with integer coeffiecients that have degree n. Using the fact that every polynomial has a finite number of roots. Show that A_n is countable. The Attempt at a Solution So an nth degree polynomial has n...
  24. I

    Are the set of all the polynomials of degree 2 a vector space?

    Homework Statement Let P denote the set of all polynomials whose degree is exactly 2. Is P a vector space? Justify your answer. Homework Equations (the numbers next to the a's are substripts P is defined as ---->A(0)+A(1)x+A(2)x^2 The Attempt at a Solution I really don't...
  25. J

    Finding general difference polynomials' recurrance relation

    Hi! I have a sequence of difference polynomials (which I obtained by the method of finite differences) and I would like to find out if there is a recurrence relation between them. The generating function of general difference polynomials is given by: How would one write the...
  26. M

    Monic irreducible polynomials in valued fields

    Homework Statement I am trying to work out a solution to the following problem, where we are working in a field K complete with respect to a discrete valuation, with valuation ring \mathcal{O} and residue field k. Q: Let f(X) be a monic irreducible polynomial in K[X]. Show that if f(0) \in...
  27. A

    Hermite polynomials and Schwartz space

    Homework Statement I'm supposed to show that the Hermite Polynomials are in Schwartz space h_n = \frac{1}{\sqrt{n!}}(A^{\dagger})^n h_0 where A^{\dagger} = \frac{1}{\sqrt{2}}(-\frac{d}{dx} + x) and h_0 = \pi^{-1/4}e^{-x^2/2} Homework Equations Seminorm...
  28. M

    Polynomial Equation: Solving for x with 3 Solutions | Math Homework

    Homework Statement Find x (17-x)^2(11-x)+256-32(17-x)-64(11-x)=0 Homework Equations The Attempt at a Solution This eq has 3 solutions. I solved this by multiplication. Is this some other easier way. Perhaps to group some of the factors 17-x and 11-x. Tnx for the answer.
  29. E

    Integrating Legendre Polynomials Pl & Pm

    Homework Statement Integrate the expression Pl and Pm are Legendre polynomials Homework Equations The Attempt at a Solution Suppose that solution is equal to zero.
  30. A

    Roots of Cubic Polynomials over R

    I'm trying to prove the following, which is left unproven in something I'm reading on ruler-and-compass constructions: If ax^3+bx^2+cx+d is a polynomial over a subfield F of ℝ, and p+q\sqrt{r} is a root (with \sqrt{r}\notin F) then p-q\sqrt{r} is also a root. The theorem immediately before...
  31. C

    Challenge to the community, Squaring of polynomials conjecture

    Given polynomials of degree n > 2, such that they have the form of p(x) \ = \ x^n \ + \ a_1x^{n - 1} \ + \ a_2x^{n - 2} \ + \ a_3x^{n - 3} \ + \ ... \ + \ a_{n - 2}x^2 \ + \ a_{n - 1}x \ + \ a_n. And \ \ all \ \ of \ \ the \ \ a_i \ \ are \ nonzero \ integers \ (which...
  32. D

    Question about determinants and characteristic polynomials.

    I know this may be a very stupid question, but I would really like to know. Is the determinant and the characteristic polynomial of an equation unique? I did several textbook questions and when I look at the solutions, they end up with completely different answers. Sometimes I am wrong and see...
  33. G

    Taylor Polynomials: Exploring Different Derivations

    http://bildr.no/view/1030479 The link above, it is my own and it is a bit disorderly, I think should explain taylor polynomials. In one assignent one had an assignment to derive taylor polynomials for cost^2 If one use the derivation rules with chain one get 2t for first derivative and...
  34. I

    Linear algebra: eigenvalue & character polynomials proof

    we are given B = CAC^-1 Prove that A and B have the same characteristic polynomial given a hint: explain why ƛIn = CƛInC^-1 what I did was: B = CAC^-1 BC = CA Det(BC) = Det(CA) Det(B) Det(C) = Det(C) Det(A) Now they’re just numbers so I divide both sides by Det(C) Det(B) = Det(A)...
  35. L

    Linear algebra - big ole matrix full of polynomials

    Homework Statement My professor wrote a paper about tennis a couple of years ago and he's asked us to recreate some of his results. So I have this vector: I'm supposed to multiply it with this matrix: to get (p1, 0, 0, 0, q1). p1 is: q1 is similar but the p's and q's...
  36. M

    Orthogonality Relationship for Legendre Polynomials in Cylindrical Coordinates

    Hello everyone, Sorry if this is in the wrong sub-forum, I wasn't sure exactly where to place it. I was wondering if there is an orthogonality relationship for the Legendre polynomials P^{0}_{n}(x) that have been converted to cylindrical coordinates from spherical coordinates, similar to...
  37. R

    Removal of Polynomials From Raw Aperture Flux Time Series?

    Hello! This is my first post so forgive any errors of decorum. :o) I am a student working toward a degree in astrophysics but I'd like to jump a few years ahead when it comes to the study of exoplanets. While examining some data about the new discovery of Kepler-22b, I noticed a plotted data...
  38. S

    Jordan Forms, Nullity and Minimal Polynomials

    Homework Statement Nullity(B-5I)=2 and Nullity(B-5I)^2=5 Characteristic poly is: (λ-5)^12 Find the possible jordan forms of B and the minimal polynomials for each of these JFs. The Attempt at a Solution JFs: Jn1(5) or ... or Jni(5). Not sure how to find these jordan forms and minimal polynomials.
  39. D

    Using isomorphisms to transform polynomials to vectors.

    Does this actually work well? We won't learn isomorphisms in linear algebra, but a friend of mine showed me an example as I prefer to work with vectors and matrices rather than polynomials (All of my problem sets are with matrices and vectors). For example, if I wanted to find a basis for P3...
  40. C

    Characteristic and minimal polynomials

    Homework Statement Let V be a finite dimensional complex vector space and T be the linear operator of V. Prove that the following are equivalent a V has a basis consisting of eigenvectors of T. b T can be represented by a diagonal matrix. c all the eigenvalues of T have multiplicity...
  41. M

    Proof involving Taylor Polynomials / Lagrange Error Bound

    Homework Statement I'm given that the function f(x) is n times differentiable over an interval I and that there exists a polynomial Q(x) of degree less than or equal to n s.t. \left|f(x) - Q(x)\right| \leq K\left|x - a\right|^{n+1} for a constant K and for a \in I I am to show that Q(x)...
  42. P

    Irreducible polynomials over ring of integers

    Is it true that polynomials of the form : f_n= x^n+x^{n-1}+\cdots+x^{k+1}+ax^k+ax^{k-1}+\cdots+a where \gcd(n+1,k+1)=1 , a\in \mathbb{Z^{+}} , a is odd number , a>1, and a_1\neq 1 are irreducible over the ring of integers \mathbb{Z}...
  43. D

    Spanning sets and polynomials.

    Homework Statement Do the polynomials t^{3} + 2t + 1,t^{2} - t + 2, t^{3} +2, -t^{3} + t^{2} - 5t + 2 span P_{3}? Homework Equations N/A The Attempt at a Solution My attempt: let at^{3} + bt^{2} + ct + d be an arbitrary vector in P_{3}, then: c_{1}(t^{3} + 2t + 1) + c_{2}(t^{2} -...
  44. V

    Newton Polynomials through Specific Points

    I have completed a difference table for 4 points, x0, x1, x2, x3 and found the third degree poly that goes through these four points. Now I need to know how to make the polynomial of second degree that interpolates x0, x2, and x3. Do I just need to remake the table for 3 points, now excluding...
  45. M

    Differential Equations - Hermite Polynomials

    Homework Statement Here is the entire problem set, but (obviously) you don't have to do it all, if you could just give me a few hints on where to even start, because I am completely lost. Recall that we found the solutions of the Schrodinger equations (x^2 - \partial_x ^2) V_n(x) =...
  46. S

    Simple question regarding polynomials

    Hello all I had a simple question that I am intuitively sure I know the answer to but can't quite prove it. Suppose k is a polynomial in x and y, and k(x-1) = q for q some polynomial in y. Then is k = 0 ? How do I verify that k must be equal to 0? I can see that to just get a polynomial...
  47. E

    Solving Polynomials in $\mathbb{Z}_{n}$ | Algebra Course

    I am taking a first course in algebra and this is a problem in my textbook that has me stumped: Fix \ a \in \mathbb{Z}_{n} \ and \ f \in \mathbb{Z}_{n}[x] \ with \ \deg(f) = m. Show \ there \ is \ h_{m-1} \in \mathbb{Z}_{p}[x] \ with \ \deg(h_{m-1}) \leq (m-1) \ so \ f = a_{m}(x - a)^m +...
  48. T

    Let [itex]V= \mathbb{R}_3[x][/itex] be the vector space of polynomials

    Let V= \mathbb{R}_3[x] be the vector space of polynomials with real coefficients with degree at most 3 and let D:V\to V be the linear operator of taking derivatives, D(f)=f'. I'm trying to check the Rank-nullity theorem for this example but it doesn't seem to hold: Since D is not injective...
  49. L

    Characteristic/Minimal polynomials - Linear Algebra question

    Homework Statement Given the matrix: 0 1 0 0 0 1 12 8 -1 (sorry I don't know how to put proper matrix format) a) find polynomials a(λ)(λ+2)2+b(λ)(λ-3) = 1 (where a(λ) and b(λ) are the polynomials) The Attempt at a Solution Well the characteristic...
  50. S

    Probability of Arranging Rooks on Chessboard with Rook Polynomials

    help withe this tow Question please ? Q1: A pair of dice, one red and the other green, is rolled six times. We know that the ordered pairs (1, 1), (1, 5), (2, 4), (3, 6), (4, 2), (4, 4), (5, 1), and (5, 5) did not come up. What is the probability that every value came up on both...
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