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Lagrange's Theorem

Proposition Let H be a subgroup of G with g \in G and define a map \phi:H \rightarrow gH by \phi(h) = gh. The map \phi is bijective; hence, the number of elements in H is the same as the number of elements in gH.

Lagrange's Theorem

suggests that groups of prime order \(p\) must somehow look like \({\mathbb Z}_p\).

In fact, we can say more about when two cycles have the same length.

Condensed: the full section is in Judson, Abstract Algebra: Theory and Applications.

Ugbu a ị Enweghị kalkulata na-ewepụ nke a, ma ọ bụ na ọ nwere ike ijikwa ya. Jiri otu n'okpuru, mọọbụ pịa nke gị.

Kwụsị ọrụ gị

Akwụkwọ ndebanye n'efu na-egbakwunye ntọala n'ụdị ọmụmụ ihe ọbụla, ndepụta nke ihe ị ga-eme, nsogbu ị ga-ewepụ n'otu ebe, na onye nkụzi ị ga-ajụ banyere ihuakwụkwọ a. Akwụkwọ ndepụta ihe bụ nke ọbụla mepere maka onye ọbụla, ọbụla ma ọ bụ na ọ bụghị.

Akaụntụ Nbanye

Aịkọn ndị ahụ ejirila ebe a

Tinye ọbụla simbụl maka nkọwa zuru ezu, inyogo, na ihe ọbụla ọbụla na-egosi.

Ajụjụ ndị mmadụ jụrụ

What is a group, in plain words?

A set with one operation that is associative, has an identity, and lets every element be undone. Symmetries of any object form a group. That is where the idea came from.

What is the difference between a ring and a field?

A ring has addition and multiplication that behave like the integers (you cannot always divide); a field is a ring where every non-zero element has a reciprocal, like the rationals or the reals.

Oge nke ihuakwụkwọ a bụ nke a gbanwere site na Judson, Abstract Algebra: Theory and Applications (GFDL 1.3). E kọwaara ya na ebe a; nsogbu bụ nke anyị.

Oge Abstract Algebra