Task: Question Answering
Input (English): Let V be the set of all real polynomials p(x). Let transformations T, S be defined on V by T:p(x) -> xp(x) and S:p(x) -> p'(x) = d/dx p(x), and interpret (ST)(p(x)) as S(T(p(x))). Which of the following is true?
(A)ST = 0 (B)ST = T (C)ST = TS (D)ST - TS is the identity map of V onto itself.
Output (English): D