Question2. If $\sin (\alpha)=\frac{2}{5}$ and $\tan (\beta)=\sqrt{2}$, where $\frac{\pi}{2} \operatorname{sinsm}$ and $\frac{\pi}{2} s \beta s^{\frac{3 \pi}{2}}$, calculate $\sin (\alpha+\beta)+\sin (\alpha-\beta)$. Show at least four lines of work for fult marks. (4 Marks])
3. Determine the exact value of $\operatorname{Cos}(2 x), \operatorname{CSc}(x)=\frac{-17}{15}$ and $\frac{3 \pi}{2} 5 \times \leq 2 \pi$. Show at least three lines of work for full merts. (4 Marks)