Practice question · Put in order
Order from most constrained to least constrained curvature.
- Positive definite (all directions curve up)
- Indefinite (up in some, down in others)
- Positive semidefinite (up or flat, never down)
Hints
- Order by how strongly the curvature is constrained.
- Allowing opposite curvatures is the least constrained case.
Show the answer
- Positive definite (all directions curve up)
- Positive semidefinite (up or flat, never down)
- Indefinite (up in some, down in others)
Why
Definite is the strongest constraint (all directions agree); semidefinite allows flatness; indefinite allows opposite curvatures.
Practise Quadratic Forms
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