| Exam Board | Edexcel |
|---|---|
| Module | C2 (Core Mathematics 2) |
| Marks | 13 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Standard trigonometric equations |
| Type | Equation with non-equation preliminary part (sketch/proof/identity) |
| Difficulty | Moderate -0.3 This is a straightforward C2 question testing standard techniques: solving a sine equation with a compound angle (routine inverse sine and angle manipulation), applying the sine rule directly with given values, and finding cosine from sine using the Pythagorean identity. All parts are textbook exercises requiring recall and basic manipulation rather than problem-solving, making it slightly easier than average but not trivial due to the multi-step nature and need for careful angle work. |
| Spec | 1.05b Sine and cosine rules: including ambiguous case1.05o Trigonometric equations: solve in given intervals |
\begin{enumerate}[label=(\roman*)]
\item Solve, for $0° < x < 180°$, the equation
$$\sin (2x + 50°) = 0.6,$$
giving your answers to 1 decimal place. [7]
\item In the triangle $ABC$, $AC = 18$ cm, $\angle ABC = 60°$ and $\sin A = \frac{1}{3}$.
\begin{enumerate}[label=(\alph*)]
\item Use the sine rule to show that $BC = 4\sqrt{3}$. [4]
\item Find the exact value of $\cos A$. [2]
\end{enumerate}
\end{enumerate}
\hfill \mbox{\textit{Edexcel C2 Q8 [13]}}