Higher November 2022 Unit 1 Q20
20. The following diagram shows a sketch of \(y = \cos x\) for values of \(x\) from 0° to 360°.

Given that \(\cos 25^\circ = 0{\cdot}9063\), correct to 4 decimal places, write down all the solutions of the equation
\(\cos x = -0{\cdot}9063\)
for values of \(x\) from 0° to 360°. [2]
| Scheme | Marks | Comments |
|---|---|---|
| 155° and 205° with no other values | B2 | B1 for either angle. Check diagram. Ignore extra (correct or incorrect) values outside the required range Penalise -1 for each extra value within range (beyond 2 attempts). |