Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Linear transformations

  1. Feb 3, 2004 #1
    Let g(x) belonging to Pn-1(R) be an arbiitrary polynomial of degree n-1 or less. Show that there exists a polynomial f(x) belonging to Pn(R) such that xf''(x)-f'(x)=g(x)"

    I interpreted this question as having to prove the linear transformation T: Pn(R) --> Pn-1(R) where f(x) |--> xf''(x)-f'(x) is onto.

    If I let f(x)=a+bx+cx^2+...+zx^n
    T(f(x))=-b

    Therefore the range of T is {x} which has dimension 1. By the dimension theorem (and just looking at the results), the nullspace has dimension n. This of course is not onto.

    I think I must be interpreting the question wrong. Please help! I have a midterm tomorrow.
     
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted