AQA Further Paper 3 Discrete 2023 June — Question 9 2 marks

Exam BoardAQA
ModuleFurther Paper 3 Discrete (Further Paper 3 Discrete)
Year2023
SessionJune
Marks2
TopicGroups

9 The group \(\left( C , + _ { 4 } \right)\) contains the elements \(0,1,2\) and 3 9
    1. Show that \(C\) is a cyclic group.
      9
  1. (ii) State the group of symmetries of a regular polygon that is isomorphic to \(C\)
    9
  2. The group ( \(V , \otimes\) ) contains the elements (1, 1), (1, -1), (-1, 1) and (-1, -1) The binary operation \(\otimes\) between elements of \(V\) is defined by $$( a , b ) \otimes ( c , d ) = ( a \times c , b \times d )$$ 9
    1. Find the element in \(V\) that is the inverse of \(( - 1,1 )\)
      Fully justify your answer.
      [0pt] [2 marks]
      9
  3. (ii) Determine, with a reason, whether or not \(C \cong V\)
    \(\mathbf { 9 }\) (c) The group \(G\) has order 16
    Rachel claims that as \(1,2,4,8\) and 16 are the only factors of 16 then, by Lagrange's theorem, the group \(G\) will have exactly 5 distinct subgroups, including the trivial subgroup and \(G\) itself. Comment on the validity of Rachel's claim.
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