Test your understanding of double and half angles, t-formulas, and the auxiliary angle method.
Its question set has not been written, so there is nothing here to attempt. Nothing you have done is lost, and the lessons either side of it are unaffected.
To test yourself on this material now, use the module quiz, which covers the same content.
1. If $\cos\theta = \frac{12}{13}$ and $0 < \theta < \frac{\pi}{2}$, find $\sin(2\theta)$. (2 marks)
2. Find the exact value of $\sin(22.5°)$. (2 marks)
3. If $t = \tan\frac{\theta}{2} = \frac{1}{3}$, find $\cos\theta$. (2 marks)
4. Express $3\sin\theta + 4\cos\theta$ in the form $R\sin(\theta + \alpha)$. (3 marks)