WJEC Unit 1 2022 June — Question 5 9 marks

Exam BoardWJEC
ModuleUnit 1 (Unit 1)
Year2022
SessionJune
Marks9
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicCurve Sketching
TypePolynomial intersection with algebra
DifficultyModerate -0.8 This is a straightforward multi-part question testing basic curve intersection (solving a quadratic equation), sketching parabolas, and shading regions defined by inequalities. All techniques are routine for AS-level with no problem-solving insight required, making it easier than average but not trivial due to the multiple components.
Spec1.02i Represent inequalities: graphically on coordinate plane1.02n Sketch curves: simple equations including polynomials1.02q Use intersection points: of graphs to solve equations

The curve \(C_1\) has equation \(y = -x^2 + 2x + 3\) and the curve \(C_2\) has equation \(y = x^2 - x - 6\). The two curves intersect at the points \(A\) and \(B\).
  1. Determine the coordinates of \(A\) and \(B\). [4]
  2. On the same set of axes, sketch the graphs of \(C_1\) and \(C_2\). Clearly label the points where the two curves intersect. [3]
  3. In the diagram drawn in part (b), shade the region satisfying the following inequalities: [2] $$x > 0,$$ $$y < -x^2 + 2x + 3,$$ $$y > x^2 - x - 6.$$

The curve $C_1$ has equation $y = -x^2 + 2x + 3$ and the curve $C_2$ has equation $y = x^2 - x - 6$. The two curves intersect at the points $A$ and $B$.

\begin{enumerate}[label=(\alph*)]
\item Determine the coordinates of $A$ and $B$. [4]
\item On the same set of axes, sketch the graphs of $C_1$ and $C_2$. Clearly label the points where the two curves intersect. [3]
\item In the diagram drawn in part (b), shade the region satisfying the following inequalities: [2]
$$x > 0,$$
$$y < -x^2 + 2x + 3,$$
$$y > x^2 - x - 6.$$
\end{enumerate}

\hfill \mbox{\textit{WJEC Unit 1 2022 Q5 [9]}}