Edexcel FP2 AS 2019 June — Question 4

Exam BoardEdexcel
ModuleFP2 AS (Further Pure 2 AS)
Year2019
SessionJune
TopicGroups

  1. The set \(\{ e , p , q , r , s \}\) forms a group, \(A\), under the operation *
Given that \(e\) is the identity element and that $$p ^ { * } p = s \quad s ^ { * } s = r \quad p ^ { * } p ^ { * } p = q$$
  1. show that
    1. \(p ^ { * } q = r\)
    2. \(s ^ { * } p = q\)
  2. Hence complete the Cayley table below.
    *\(e\)\(\boldsymbol { p }\)\(\boldsymbol { q }\)\(r\)\(s\)
    \(e\)
    \(\boldsymbol { p }\)
    \(\boldsymbol { q }\)
    \(\boldsymbol { r }\)
    \(S\)
    A spare table can be found on page 11 if you need to rewrite your Cayley table.
  3. Use your table to find \(p ^ { * } q ^ { * } r ^ { * } s\) A student states that there is a subgroup of \(A\) of order 3
  4. Comment on the validity of this statement, giving a reason for your answer. \includegraphics[max width=\textwidth, alt={}, center]{989d779e-c40a-4658-ad98-17a37ab1d9e1-11_2464_74_304_36}
    Only use this grid if you need to rewrite the Cayley table.
    *\(e\)\(\boldsymbol { p }\)\(\boldsymbol { q }\)\(r\)\(s\)
    \(e\)
    \(\boldsymbol { p }\)
    \(\boldsymbol { q }\)
    \(\boldsymbol { r }\)
    \(S\)