SPS SPS SM 2024 October — Question 4 6 marks

Exam BoardSPS
ModuleSPS SM (SPS SM)
Year2024
SessionOctober
Marks6
TopicDiscriminant and conditions for roots
TypeShow discriminant inequality, then solve
DifficultyModerate -0.3 This is a straightforward discriminant problem requiring rearrangement to standard form, applying b²-4ac < 0, and solving a quadratic inequality. While it involves multiple steps (6 marks total), each step follows standard A-level procedures with no novel insight required. The algebraic manipulation is routine, making it slightly easier than average.
Spec1.02d Quadratic functions: graphs and discriminant conditions1.02g Inequalities: linear and quadratic in single variable1.02h Express solutions: using 'and', 'or', set and interval notation

The quadratic equation \(kx^2 + 2kx + 2k = 3x - 1\), where \(k\) is a constant, has no real roots.
  1. Show that \(k\) satisfies the inequality $$4k^2 + 16k - 9 > 0.$$ [4]
  2. Hence find the set of possible values of \(k\). Give your answer in set notation. [2]

The quadratic equation $kx^2 + 2kx + 2k = 3x - 1$, where $k$ is a constant, has no real roots.

\begin{enumerate}[label=(\alph*)]
\item Show that $k$ satisfies the inequality
$$4k^2 + 16k - 9 > 0.$$ [4]

\item Hence find the set of possible values of $k$. Give your answer in set notation. [2]
\end{enumerate}

\hfill \mbox{\textit{SPS SPS SM 2024 Q4 [6]}}