| Exam Board | OCR MEI |
|---|---|
| Module | C2 (Core Mathematics 2) |
| Year | 2008 |
| Session | January |
| Marks | 3 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Trigonometric equations in context |
| Type | Simplify or verify trig identity with acute angle |
| Difficulty | Moderate -0.8 This is a straightforward application of the Pythagorean identity using a right-angled triangle with sides 1, 2, √5. It requires only basic trigonometric knowledge and simple algebraic manipulation, making it easier than average for A-level. The 'show that' format removes any problem-solving element. |
| Spec | 1.05j Trigonometric identities: tan=sin/cos and sin^2+cos^2=1 |
3 You are given that $\tan \theta = \frac { 1 } { 2 }$ and the angle $\theta$ is acute. Show, without using a calculator, that $\cos ^ { 2 } \theta = \frac { 4 } { 5 }$.
\hfill \mbox{\textit{OCR MEI C2 2008 Q3 [3]}}