maths.free › Functional Analysis › Normed and Banach spaces

Normed and Banach spaces

Vector spaces with a length; completeness; the classical sequence and function spaces.

A norm measures length; a Banach space is a normed space with no missing limits. ℓ^p, L^p and the continuous functions with the sup norm are the standard examples. Picture it: the unit balls for different norms, a diamond, a circle, a square. Think it: completeness is what lets you solve equations by successive approximation (the contraction mapping theorem).

Isibonelo esisebenza · sqrt(3^2 + 4^2)

Arithmetic · Arithmetic

Evaluate sqrt(3^2 + 4^2)

\sqrt{3^{2} + 4^{2}}

Isigaba

  1. \sqrt{3^{2} + 4^{2}} = \sqrt{9 + 4^{2}}

    Power: 3^2 = 9.

  2. \sqrt{9 + 4^{2}} = \sqrt{9 + 16}

    Power: 4^2 = 16.

  3. \sqrt{9 + 16} = \sqrt{25}

    Add: 9 + 16 = 25.

  4. \sqrt{25} = 5

    Simplify.

Bonisa impendulo
5

Manje Khetha izinkinga, noma ubhale noma udwebe zakho. Isigaba ngasinye, isithombe, impendulo ifihlakele kuze kube ubuza.

Qhubeka usebenza

I-akhawunti emahhala ifaka iziphawulo kulesifundo ngasinye, irekhodi lokuthi yini oqedile, izinkinga zakho ezixazululiwe endaweni eyodwa, nodokotela owaziyo ongabuza mayelana nalekhasi. I-matematics ivulekile kubo bonke, noma ngabe babhalise noma cha.

Bhala Ngena

Amaphawu asetshenziswa lapha

Chofoza noma yiluphi uphawu lwesibonakaliso ukuze uthole ukuchaza okuphelele, isithombe, kanye nokuthi iyiphi inhlamvu ekhona ekhuluma ngaso.

Indlela: Normed and Banach spaces

  1. Power: 3^2 = 9.
  2. Power: 4^2 = 16.
  3. Add: 9 + 16 = 25.
  4. Simplify.

Imibuzo abantu bebuza

What is a Hilbert space?

A vector space with an inner product (so lengths and angles make sense) that is complete (no missing limit points). Square-integrable functions form one; quantum states live in one.

Okuningi Functional Analysis

Hilbert spaces and the spectral theorem