AQA C2 2009 June — Question 1 5 marks

Exam BoardAQA
ModuleC2 (Core Mathematics 2)
Year2009
SessionJune
Marks5
PaperDownload PDF ↗
Mark schemeDownload PDF ↗
TopicSine and Cosine Rules
TypeSequential triangle calculations (basic)
DifficultyModerate -0.8 This is a straightforward two-part question testing basic trigonometry. Part (a) requires a direct application of the cosine rule to find an angle (routine calculation), and part (b) uses the standard area formula (1/2)ab sin C. Both are standard textbook exercises with no problem-solving or insight required, making this easier than average for A-level.
Spec1.05b Sine and cosine rules: including ambiguous case1.05c Area of triangle: using 1/2 ab sin(C)

The triangle \(ABC\), shown in the diagram, is such that \(AB = 7\) cm, \(AC = 5\) cm, \(BC = 8\) cm and angle \(ABC = \theta\). \includegraphics{figure_1}
  1. Show that \(\theta = 38.2°\), correct to the nearest \(0.1°\). [3]
  2. Calculate the area of triangle \(ABC\), giving your answer, in cm\(^2\), to three significant figures. [2]

Question 1:
1
Question 1:
1
The triangle $ABC$, shown in the diagram, is such that $AB = 7$ cm, $AC = 5$ cm, $BC = 8$ cm and angle $ABC = \theta$.

\includegraphics{figure_1}

\begin{enumerate}[label=(\alph*)]
\item Show that $\theta = 38.2°$, correct to the nearest $0.1°$. [3]
\item Calculate the area of triangle $ABC$, giving your answer, in cm$^2$, to three significant figures. [2]
\end{enumerate}

\hfill \mbox{\textit{AQA C2 2009 Q1 [5]}}