Thank you for pointing this out. You’re right that the bounds should be $latex -1$ to $latex 1$, but as the integrand is symmetric I went ahead and doubled the integral and replaced the bounds with $latex 0$ to $latex 1$ in the same step. This is the additional $latex 2$ in front of the integral, and the reason why I separated that $latex 2$ from the other $latex 2$ factors.

]]>It should be -1 to +1

]]>you have a good simple way of explaining! :)

words like “well behaved” etc really take down the intimidation level ! :P ]]>

I don’t see how the MVT for integrals gets you out of this, but I’ll think about it some more, since I agree it’d be a nicer proof than the standard one if it can be fixed.

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