Exam Questions & Step-by-Step Markschemes (6 Problems)
Question 1 • 2024
4 Marks
Prove that:\n\n \frac{\sin x - \sin y}{\cos x + \cos y} = \tan\left(\frac{x - y}{2}\right)
Answer: \text{LHS} = \text{RHS} \quad \text{(Proved)}
Question 2 • 2024
4 Marks
Prove that: \cos 20^\circ \cos 40^\circ \cos 60^\circ \cos 80^\circ = \frac{1}{16}
Answer: \text{LHS} = \text{RHS} = \frac{1}{16}
Question 3 • 2024
4 Marks
Prove the following identity: \cos 20^\circ \cos 40^\circ \cos 60^\circ \cos 80^\circ = \frac{1}{16}
Answer: \text{Identity Proved: } \frac{1}{16}
Question 4 • 2024
4 Marks
Prove that: \cos 20^\circ \cos 40^\circ \cos 60^\circ \cos 80^\circ = \frac{1}{16}
Answer: \text{Hence Proved, } \text{LHS} = \frac{1}{16}
Question 5 • 2023
4 Marks
Prove that: \frac{\sin 5x - 2\sin 3x + \sin x}{\cos 5x - \cos x} = \tan x
Answer: \text{Hence Proved, } \text{LHS} = \tan x
Question 6 • 2024
5 Marks
Prove that: \cos 20^\circ \cos 40^\circ \cos 60^\circ \cos 80^\circ = \frac{1}{16}
Answer: \frac{1}{16}