- #1
neelakash
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Homework Statement
int x^m*P_n(x) dx=0 where integration is from (-1) to (+1).Given m<n
Homework Equations
The Attempt at a Solution
I took integrand F(x) and saw that F(-x)=(-1)^(m+n)*F(x)
should that help anyway?
neelakash said:Homework Statement
int x^m*P_n(x) dx=0 where integration is from (-1) to (+1).Given m<n
Homework Equations
The Attempt at a Solution
I took integrand F(x) and saw that F(-x)=(-1)^(m+n)*F(x)
should that help anyway?
neelakash said:OK,you were correct.Because,
the Legendre polynomials are complete on [-1,1], so:
x^m=a linear combination of P_0,P_1,P_2,...P_m
where m<n
Hence the result follow directly from orthogonality.
The purpose of integrating Legendre polynomials is to find the area under the curve formed by the polynomial. This is useful in many applications such as solving differential equations and calculating probabilities in statistics.
The formula for integrating Legendre polynomials is given by the Gauss-Legendre quadrature formula. This formula uses a weighted sum of function values at specific points to approximate the integral.
The limits of integration for Legendre polynomials are typically from -1 to 1, as these polynomials are defined over this range. However, the bounds can be adjusted to fit the specific problem at hand.
Legendre polynomials are used in physics to solve problems involving spherical symmetry, such as finding the potential and electric fields of charged particles in a spherical shell. They are also used in quantum mechanics to solve the Schrödinger equation for certain potentials.
Yes, Legendre polynomials can be integrated analytically using a variety of methods such as the Gauss-Legendre quadrature formula or the method of undetermined coefficients. However, for higher order polynomials, it may be more efficient to use numerical methods to approximate the integral.