Edexcel C2 — Question 4 6 marks

Exam BoardEdexcel
ModuleC2 (Core Mathematics 2)
Marks6
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicTrig Graphs & Exact Values
TypeSketch two trig curves and count intersections/solutions
DifficultyModerate -0.3 This is a straightforward C2 graphical question requiring sketches of two standard trigonometric functions with simple transformations (horizontal stretch/compression), then counting intersections. The sketching is routine for C2 level, and identifying solutions from a graph requires minimal problem-solving beyond visual inspection. Slightly easier than average due to its procedural nature.
Spec1.05f Trigonometric function graphs: symmetries and periodicities1.05k Further identities: sec^2=1+tan^2 and cosec^2=1+cot^2

  1. Sketch on the same diagram the graphs of \(y = \sin 2x\) and \(y = \tan \frac{x}{2}\) for \(x\) in the interval \(0 \leq x \leq 360°\). [4]
  2. Hence state how many solutions exist to the equation $$\sin 2x = \tan \frac{x}{2},$$ for \(x\) in the interval \(0 \leq x \leq 360°\) and give a reason for your answer. [2]

AnswerMarks Guidance
(a) Sketch showing \(y = \tan \frac{x}{2}\)B2
Sketch showing \(y = \sin 2x\)B2
(b) 4 solutionsB1
the graphs intersect at 4 pointsB1 (6)
**(a)** Sketch showing $y = \tan \frac{x}{2}$ | B2 |
Sketch showing $y = \sin 2x$ | B2 |

**(b)** 4 solutions | B1 |
the graphs intersect at 4 points | B1 | (6)
\begin{enumerate}[label=(\alph*)]
\item Sketch on the same diagram the graphs of $y = \sin 2x$ and $y = \tan \frac{x}{2}$ for $x$ in the interval $0 \leq x \leq 360°$. [4]
\item Hence state how many solutions exist to the equation
$$\sin 2x = \tan \frac{x}{2},$$
for $x$ in the interval $0 \leq x \leq 360°$ and give a reason for your answer. [2]
\end{enumerate}

\hfill \mbox{\textit{Edexcel C2  Q4 [6]}}