Why is the first one not an inner product but the second one is?

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$\langle p,q \rangle = \int_{-1}^1 p^\ast(t)q(t)tdt$ over $\mathbb{P}$

$\langle p,q \rangle = \int_{-1}^1 p^\ast(t)q(t)(t+1)dt$ over $\mathbb{P}$

I believe positivity works for both of them, and I am unsure of how to show the other ways of proving an inner product.

The star denotes complex conjugate.

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Positivity condition fails.

Take p,q as 1.

$<p,p>=0$ for first case as

$\int_{-1}^1 t= \frac{t^2}{2}|_{-1}^1$

$t^2=1-1=0$