1 1 π
arctan arctan
4. (a) Show that 2 3 4 .
(2)
(b) Hence, or otherwise, find the value of arctan (2) + arctan (3).
(3)
(Total 5 marks)
5. A system of equations is given by
cos x + cos y = 1.2
sin x + sin y = 1.4.
(a) For each equation express y in terms of x.
(2)
(b) Hence solve the system for 0 < x < p, 0 < y < p.
(4)
(Total 6 marks)
7. (a) Sketch the curve f(x) = sin 2x, 0 ≤ x ≤ π.
(2)
(b) Hence sketch on a separate diagram the graph of g(x) = csc 2x, 0 ≤ x ≤ π, clearly stating
the coordinates of any local maximum or minimum points and the equations of any
asymptotes.
(5)
(c) Show that tan x + cot x ≡ 2 csc 2x.
(3)
(d) Hence or otherwise, find the coordinates of the local maximum and local minimum points
π
on the graph of y = tan 2x + cot 2x, 0 ≤ x ≤ 2 .
(5)
π
(e) Find the solution of the equation csc 2x = 1.5 tan x – 0.5, 0 ≤ x ≤ 2 .
1
(6)
(Total 21 marks)
8. Solve sin 2x = 2 cos x, 0 ≤ x ≤ π.
(Total 6 marks)
3
10. Given that tan 2θ = 4 , find the possible values of tan θ.
(Total 5 marks)
12. (a) If sin (x – α) = k sin (x + α) express tan x in terms of k and α.
(3)
1
(b) Hence find the values of x between 0° and 360° when k = 2 and α = 210°.
(6)
(Total 9 marks)
2
13. The angle θ satisfies the equation 2 tan θ – 5 sec θ – 10 = 0, where θ is in the second quadrant.
Find the value of sec θ.
(Total 6 marks)