| Exam Board | Edexcel |
|---|---|
| Module | C2 (Core Mathematics 2) |
| Marks | 13 |
| Paper | 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 linear trigonometric equation with a restricted domain (routine but requires careful angle manipulation), and applying the sine rule plus Pythagorean identity. All steps are procedural with no problem-solving insight required, making it slightly easier than average but not trivial due to the multi-step nature and exact value work. |
| Spec | 1.05b Sine and cosine rules: including ambiguous case1.05j Trigonometric identities: tan=sin/cos and sin^2+cos^2=11.05o 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 Q33 [13]}}