AQA Further Paper 3 Discrete 2021 June — Question 5

Exam BoardAQA
ModuleFurther Paper 3 Discrete (Further Paper 3 Discrete)
Year2021
SessionJune
TopicGroups

5
  1. Describe the conditions necessary for a set of elements, \(S\), under a binary operation * to form a group.
    5
  2. In the multiplicative group of integers modulo 13, the group \(G\) is defined as $$G = \left( \langle 10 \rangle , \times _ { 13 } \right)$$ 5
    1. Explain why \(G\) is an abelian group.
      5
  3. (ii) Find the order of \(G\).
    5
  4. State the identity element of \(G\) and prove it is an identity element. Fully justify your answer.
    5
  5. Find all the proper non-trivial subgroups of \(G\), giving your answers in the form \(\left( \langle g \rangle , \times _ { 13 } \right)\), where \(g\) is an integer less than 13