Let x be in R^n and Q in Mat(R,n) where Q is hermitian and negative definite. Let (.,.) be the usual euclidian inner product.(adsbygoogle = window.adsbygoogle || []).push({});

I need to prove the following inequality:

(x,Qx) <= a(x,x)

where "a" is the maximum eigenvalue of Q.

Any idea?

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# Inequality on inner product

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