--%>

Properties of a group

How can we say that the pair (G, o) is a group. Explain the properties which proof it.

E

Expert

Verified

Let G be a set and suppose that o is a binary operation on G. We say that the pair (G; o) is a group if it has the following properties.

(i) The operation o is associative; that is, (g o h) o k = g o (h o k) for all g; h; k ≡ G.

(ii) There exists an identity for o ; that is, there exists e ≡ G such that g o e = e o g = g for all g ≡ G.

(iii) There exist inverses for o ; that is, for each g ≡ G, there exists g-1≡ G such that
g o g-1 = g-1 o g = e:

There is another property implicit in this de nition which it is useful to give a name to. Instead of saying that o is a binary operation on G, we can say that the law of closure holds for o, meaning that when o acts on two elements of G the result is also in G.

Most of the groups (G; o) we study will also have the following property.

(iv) The operation o is commutative; that is, g o h = h o g for all g; h ≡ G.

A group with this property is called commutative or, more usually, abelian, after the Norwegian mathematician Niels Henrik Abel (1802{1829).

   Related Questions in Mathematics

  • Q : Solve each equation by factoring A

    A college student invested part of a $25,000 inheritance at 7% interest and the rest at 6%.  If his annual interest is $1,670 how much did he invest at 6%?  If I told you the answer is $8,000, in your own words, using complete sentences, explain how you

  • Q : Who derived the Black–Scholes Equation

    Who derived the Black–Scholes Equation?

  • Q : Problem on Datalog for defining

    The focus is on  the use of Datalog for defining properties  and queries on graphs. (a) Assume that P is some property of graphs  definable in the Datalog. Show that P is preserved beneath extensions  and homomo

  • Q : Where would we be without stochastic

    Where would we be without stochastic or Ito^ calculus?

  • Q : Budgeted cash disbursements The ABC

    The ABC Company, a merchandising firm, has budgeted its action for December according to the following information: • Sales at $560,000, all for cash. • The invoice cost for goods purc

  • Q : Econ For every value of real GDP,

    For every value of real GDP, actual investment equals

  • Q : What is the probability that the film

    T.C.Fox, marketing director for Metro-Goldmine Motion Pictures, believes that the studio's upcoming release has a 60 percent chance of being a hit, a 25 percent chance of being a moderate success, and a 15 percent chance of being a flop. To test the accuracy of his op

  • Q : Test Please read the assignment

    Please read the assignment carefully and confirm only if you are 100% sure. Please go through below mentioned guidelines and penalties: • Your solution must be accurate and complete. • Please do not change Subject Title of the Email. • Penalty clause will be applied in case of delayed or plag

  • Q : Problem on budgeted cash collections

    XYZ Company collects 20% of a month's sales in the month of sale, 70% in the month following sale, and 5% in the second month following sale. The remainder is not collectible. Budgeted sales for the subsequent four months are:     

  • Q : Statistics Caterer determines that 37%

    Caterer determines that 37% of people who sampled the food thought it was delicious. A random sample of 144 out of population of 5000. The 144 are asked to sample the food. If P-hat is the proportion saying that the food is delicious, what is the mean of the sampling distribution p-hat?