Proving Hermite Equation with Hermite Polynomials

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Im stuck on this question :(


The Hermite polynomials can be defined through

\displaystyle{F(x,h) = \sum^{\infty}_{n = 0} \frac{h^n}{n!}H_n(x)}

Prove that the H_n satisfy the hermite equation

\displaystyle{H''_n(x) - 2xH'_n(x) + 2nH_n(x) = 0}

Using

\displaystyle{\sum^{\infty}_{n = 0} \frac{h^n}{n!}nH_n(x) = h\frac{\partial}{\partial h}F(x,h)}

Can someone give me a bit of a push in the right direction?
 
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Who's F(x,h) ...?

IIRC, it has to have some exponential, right...?

Daniel.
 
No Name Required said:
Im stuck on this question :(


The Hermite polynomials can be defined through

\displaystyle{F(x,h) = \sum^{\infty}_{n = 0} \frac{h^n}{n!}H_n(x)}

Prove that the H_n satisfy the hermite equation

\displaystyle{H''_n(x) - 2xH'_n(x) + 2nH_n(x) = 0}

Using

\displaystyle{\sum^{\infty}_{n = 0} \frac{h^n}{n!}nH_n(x) = h\frac{\partial}{\partial h}F(x,h)}

Can someone give me a bit of a push in the right direction?

What's wrong with "just do it!"? Just go ahead and differentiate that sum, term by term, (your hint essentially says that you can do that), plug into the differential equation and see what happens.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...

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