If 𝐴 is indefinite and 𝐵 is positive definite, then 𝐴+𝐵 is indefinite.

robbbiehu 2022-10-16 Answered
If 𝐴 is indefinite and 𝐵 is positive definite, then 𝐴+𝐵 is indefinite.
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Answers (1)

Ramiro Sosa
Answered 2022-10-17 Author has 13 answers
Counterexample: If A = [ 1 0 0 1 ] , we can have B = I 2 and A + B is positive semidefinite.
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