4.7/



Main Idea

  1. What?
    • To Measure Accuracy:

    • The Coefficients \(c_1, c_2, ... , c_n\) in the approximation formula are \(\ \ \ \ \ \ \ \ \ \ \ \ \ \\) ,
      and,
      The Nodes \(x_1, x_2, ... , x_n\) are restricted by/to \(\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \\)
      This gives,
      The number of Parameters to choose is \(\ \ \ \ \ \ \ \ \ \ \ \ \ \\)

    • If the coefficients of a polynomial are considered parameters,

      This, then, is

  2. Why?

Legendre Polynomials

  1. What?
  2. Why?
  3. Properties:
    1. The roots of these polynomials are:
  4. The first Legendre Polynomials:
    \(P_0(x) = \ \ \ \ \ , \ \ \ \ \ \ \ \ \ \ \ \ \ \ P_1(x) = \ \ \, \ \ \ \ \ \ \ \ \ \ \ \ \ \ P_2(x) = \ \ \ \ \ \ \ \ \ \ ,\)
    \(P_3(x) = \ \ \ \ \ \ \ \ ,\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ P_4(x) = \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \\)
  5. Determining the nodes:
    • PROOF:

    The nodes \(x_1, x_2, ... , x_n\) needed to


Gaussian Quadrature on Arbitrary Intervals

  1. What?
  2. The Change of Variables:
  3. Gaussian quadrature [arbitrary interval]: