Page 200 - Mathematics_Form_Two

Trigonometry

19. Evaluate each of the following 24. If P is the point ( – 3, 8), find the sine,
expressions without using a cosine, and tangent of the obtuse
calculator: angle between OP and the x-axis,

(a) tan 60 sin 30° ° where O is the point at (0, 0).
sin 45° 25. Express each of the following in
FOR ONLINE READING ONLY
sin 30 cos 60° tan 30° ° terms of an acute angle:
Mathematics for Secondary Schools (c) sin 45 tan 60° cos 30° ° 26. From a certain point X, Hamisi

(b)
(a) sin 238º

(b) cos ( – 263º)
(c) tan ( – 36º).
(d)

(e) tan ( −300°) −tan 120°
(f)

of the top of a tall building to be
40º. Moving 50 m further away to
20. If α and β are complementary observes that the angle of elevation
angles and sin α = 3 , find the a point Y on a level road, he notices
sinα
value of: 5 the angle of elevation to be 29º.
(a) cos α (b) tan β Find:
(a) The distance of Y from the
21. Using a calculator, find the value of bottom of the building.
each of the following: (b) The height of the building.
(a) sin 192º (d) sin (–15º)
(b) cos 224º (e) cos ( – 129º) 27. The angles of elevation of a

(c) tan 321º (f) tan ( – 310º) balloon from two points, A and B
22. Find the angles between 0º and 360º that are 0.3 km apart are 62º and
which satisfy each of the following 48º, respectively, as shown in the
equations: following figure. If the balloon is
(a) sin θ = – 0.2468 vertically above the line AB, find its

(b) cos θ = 0.3579 distance above the line AB.
(c) tan α = –2.356.

23. Find the angles between – 360º
and 360º which satisfy each of the
following equations:
(a) sin θ = 0.1234

(b) cos θ = – 0.5678

(c) tan θ = 0.3546.

194
Student's Book Form Two

11/10/2024 20:14:25
MATHEMATIC F2 v5.indd 194 11/10/2024 20:14:25
MATHEMATIC F2 v5.indd 194