Edexcel P2 2020 January — Question 3 8 marks

Exam BoardEdexcel
ModuleP2 (Pure Mathematics 2)
Year2020
SessionJanuary
Marks8
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicFactor & Remainder Theorem
TypeTrigonometric substitution equations
DifficultyStandard +0.3 This is a straightforward multi-part question combining routine factor theorem application, polynomial factorization by division, and a simple trigonometric substitution. Part (a) is pure verification, part (b) is standard algebraic division followed by factoring a quadratic, and part (c) only requires substituting tan θ = x, solving for x values, then applying arctan in the specified range. No novel insight required, just methodical application of standard techniques.
Spec1.02j Manipulate polynomials: expanding, factorising, division, factor theorem1.05o Trigonometric equations: solve in given intervals

3. $$f ( x ) = 6 x ^ { 3 } + 17 x ^ { 2 } + 4 x - 12$$
  1. Use the factor theorem to show that ( \(2 x + 3\) ) is a factor of \(\mathrm { f } ( x )\).
  2. Hence, using algebra, write \(\mathrm { f } ( x )\) as a product of three linear factors.
  3. Solve, for \(\frac { \pi } { 2 } < \theta < \pi\), the equation $$6 \tan ^ { 3 } \theta + 17 \tan ^ { 2 } \theta + 4 \tan \theta - 12 = 0$$ giving your answers to 3 significant figures.

3.

$$f ( x ) = 6 x ^ { 3 } + 17 x ^ { 2 } + 4 x - 12$$
\begin{enumerate}[label=(\alph*)]
\item Use the factor theorem to show that ( $2 x + 3$ ) is a factor of $\mathrm { f } ( x )$.
\item Hence, using algebra, write $\mathrm { f } ( x )$ as a product of three linear factors.
\item Solve, for $\frac { \pi } { 2 } < \theta < \pi$, the equation

$$6 \tan ^ { 3 } \theta + 17 \tan ^ { 2 } \theta + 4 \tan \theta - 12 = 0$$

giving your answers to 3 significant figures.

\begin{center}

\end{center}
\end{enumerate}

\hfill \mbox{\textit{Edexcel P2 2020 Q3 [8]}}