| Exam Board | OCR MEI |
|---|---|
| Module | C2 (Core Mathematics 2) |
| Marks | 5 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Trigonometric equations in context |
| Type | Solve double/multiple angle equation |
| Difficulty | Moderate -0.8 This is a straightforward C2 question requiring basic graph sketching of standard trig functions and solving a simple trig equation using the graph or standard methods. The double angle adds minimal complexity, and finding cos(2x)=0.5 involves routine application of inverse cosine and considering multiple solutions in the given range. |
| Spec | 1.05f Trigonometric function graphs: symmetries and periodicities1.05o Trigonometric equations: solve in given intervals |
Question 10:
(ii) Sketch of correct shape
G1
Correct period and amplitude
G1
Period halved for $y = \cos 2x$; amplitude unchanged
G1
Note: Not ruled lines; need 1 and $-1$ indicated; nos. on horiz axis not needed if one period shown
(iii) $30°$, $150°$, $210°$
B2
Note: B1 for 2 of these, ignore extras outside range.10 (i) Sketch the graph of $y = \cos x$ for $0 ^ { \circ } \leqslant x \leqslant 360 ^ { \circ }$.\\
On the same axes, sketch the graph of $y = \cos 2 x$ for $0 ^ { \circ } \leqslant x \leqslant 360 ^ { \circ }$. Label each graph clearly.\\
(ii) Solve the equation $\cos 2 x = 0.5$ for $0 ^ { \circ } \leqslant x \leqslant 360 ^ { \circ }$.\\
\hfill \mbox{\textit{OCR MEI C2 Q10 [5]}}