TRIG - Worksheet PDF
TRIG - Worksheet PDF
TRIG - Worksheet PDF
The size of
PÔA is θ radians.
(c) Using your results from part (a) and part (b), show that sin θ < θ < tan θ.
(2)
(Total 5 marks)
3. The points P and Q lie on a circle, with centre O and radius 8 cm, such that PÔQ = 59°.
Find the area of the shaded segment of the circle contained between the arc PQ and
the chord [PQ].
(Total 5 marks)
5. (a) Show that sin 2 nx = sin((2n + 1)x) cos x – cos((2n + 1)x) sin x.
(2)
sin 2nx
cos x + cos 3x + cos 5x + ... + cos((2n – 1)x) = ,
2 sin x
for all n +
, sin x ≠ 0.
(12)
1
(c) Solve the equation cos x + cos 3x = , 0 < x < π.
2
(6)
(Total 20 marks)
π π
6. If x satisfies the equation sin x + = 2 sin x sin , show that 11 tan x = a + b 3 ,
3 3
where a, b +
.
(Total 6 marks)
8. Consider the triangle ABC where BÂC = 70°, AB = 8 cm and AC = 7 cm. The point D on the
BD
side BC is such that = 2.
DC
Determine the length of AD.
(Total 6 marks)
π
10. Consider the function f : x → − arccos x .
4
(b) Determine an expression for the inverse function, f–1, and write down its domain.
(4)
(Total 8 marks)
(b) Hence, find the two possible values of AC, giving your answers correct to two decimal
places.
(4)
(Total 6 marks)
Consider the shaded regions with areas A and B. Given that A : B = 2 : 1, find the exact value of
the ratio R : r.
(Total 5 marks)
15. Find, in its simplest form, the argument of (sin + i (1− cos ))2 where is an acute angle.
(Total 7 marks)
(b) Hence, by using Pythagoras’ Theorem in the triangle BCD, prove the cosine rule for the
triangle ABC.
(4)
Find AC.
(Total 7 marks)
5
19. The obtuse angle B is such that tan B = − . Find the values of
12
(a) sin B;
(1)
(b) cos B;
(1)
3
20. Given that tan 2θ = , find the possible values of tan θ.
4
(Total 5 marks)
1
(b) Hence find the values of x between 0° and 360° when k = and α = 210°.
2
(6)
(Total 9 marks)
22. The angle θ satisfies the equation 2 tan2 θ – 5 sec θ – 10 = 0, where θ is in the second quadrant.
Find the value of sec θ.
(Total 6 marks)
23. A farmer owns a triangular field ABC. The side [AC] is 104 m, the side [AB] is 65 m and the
angle between these two sides is 60°.
(b) Find the area of the field in the form p 3 , where p is an integer.
(3)
Let D be a point on [BC] such that [AD] bisects the 60° angle. The farmer divides the field into
two parts by constructing a straight fence [AD] of length x metres.
65x
(c) (i) Show that the area o the smaller part is given by and find an expression for
4
the area of the larger part.