(a)[5]
With all required working shown, solve $\sec \alpha \cosec \alpha = 7$ for $0^\circ < \alpha < 90^\circ$.
(b)[4]
With all required working shown, solve $\sin(\beta + 20^\circ) + \sin(\beta - 20^\circ) = 6 \cos \beta$ for $0^\circ < \beta < 90^\circ$.