Show that the Hermite polynomials H2(x) and H3(x).

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SUMMARY

The discussion focuses on demonstrating the orthogonality of the Hermite polynomials H2(x) and H3(x) over the interval x ∈ [-L, L], where L > 0. The specific polynomials are defined as H2(x) = 4x² - 2 and H3(x) = 8x³ - 12x. The integral to evaluate is ∫_{-L}^L{(4x²-2)(8x³-12x)dx}=0, which confirms their orthogonality. A key insight is that the product of H2 and H3 must be an odd function for orthogonality to hold over the arbitrary interval.

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Hi guys. I am new, and i need help badly. I have been asked this question and I have no idea how to do it. Any help would be appreciated!



Show that the Hermite polynomials H2(x) and H3(x) are orthogonal on
x € [-L, L], where L > 0 is a constant,
H2(x) = 4x² - 2 and H3(x) = 8x³ - 12x

Thanks in advance.
 
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You need to show that

\int_{-L}^L{(4x^2-2)(8x^3-12x)dx}=0

This seems an easy integral...

Or do you consider another inner product??
 
Yes you are correct. THanks you. I believe I have solved the problem correctly.
 
One thing that's worth pointing out about this problem is that while there are other ways for functions to be orthogonal over a specific interval (like [-1,1] for example), the only way possible for functions to be orthogonal over the arbitrary interval [-L,L] is if their product is an odd function.

So the original question is equivalent to showing that the product of H2 and H3 is an odd function.
 

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