SPS SPS SM 2025 October — Question 4

Exam BoardSPS
ModuleSPS SM (SPS SM)
Year2025
SessionOctober
TopicArithmetic Sequences and Series

  1. (a) A sequence has terms \(u _ { 1 } , u _ { 2 } , u _ { 3 } , \ldots\) defined by \(u _ { 1 } = 3\) and \(u _ { n + 1 } = u _ { n } ^ { 2 } - 5\) for \(n \geqslant 1\).
    1. Find the values of \(u _ { 2 } , u _ { 3 }\) and \(u _ { 4 }\).
    2. Describe the behaviour of the sequence.
      (b) The second, third and fourth terms of a geometric progression are 12,8 and \(\frac { 16 } { 3 }\). Determine the sum to infinity of this geometric progression.
      [0pt] [BLANK PAGE]
    3. In this question you must show detailed reasoning.
      \includegraphics[max width=\textwidth, alt={}, center]{2fa9e78c-8210-456c-9b70-5378609ac47d-08_464_645_210_283}
    The diagram shows the cuboid \(A B C D E F G H\) where \(A D = 3 \mathrm {~cm} , A F = ( 2 x + 1 ) \mathrm { cm }\) and \(D C = ( x - 2 ) \mathrm { cm }\). The volume of the cuboid is at most \(9 \mathrm {~cm} ^ { 3 }\).
    Find the range of possible values of \(x\). Give your answer in interval notation.
    [0pt] [BLANK PAGE]