Unit 3 Booklet

(a) y = 3sinx° (b) y = 4cosx° (c) y = tan 3x°
(d) y = 10sin 3x° (e) y = 12cos 2x° (f) y = 0á7sin 4x°
(g) y = 1á2cos 4x° (h) y = 30sin 6x° (i) y = 100cos 5x°
(j) y = Ðsinx° (k) y = Ð6sin 1 / 2 x° (l) y = Ð20cos 3x°
3. Make neat sketches of the following over the given range of values:
(a) y = 60sin 2x° 0 £ x £ 360 (b) y = 2á5cos 3x° 0 £ x £ 360
(c) y = 40sin 4x° 0 £ x £ 180 (d) y = Ð2cos 6x° 0 £ x £ 180
(e) y = Ð15sin 8x° 0 £ x £ 180 (f) y = 1á8cos 30x° 0 £ x £ 12
Exercise 2B
1. Write down the equations of the trigonometric functions in the form y = k sin(x Ð a)° or
y = k cos(x Ð a)° represented by the following graphs:
(a)
(b)
y
y
5
8
Ð30°
90° 180° 270° 360°
x
Ð20°
90° 180° 270° 360° x
Ð5
Ð8
(c)
y
5
(d)
y
0á6
10°
90° 180° 270° 360°
x
40°
90° 180° 270° 360°
x
Ð5
Ð0á6
(e)
y
4
(f)
y
15
35°
90° 180° 270° 360° x
Ð70°
90° 180° 270° 360°
x
Ð4
Ð15
2. Make neat sketches of the following trigonometric functions, showing clearly:
(i) where each graph cuts the x - axis. (ii) the maximum and minimum values.
(a) y = 10sin(x Ð 15)° (b) y = 1á4 cos(x Ð 20)° (c) y = 15sin(x + 10)°
(d) y = 2á4 cos(x + 30)° (e) y = 300sin(x Ð 80)° (f) y = tan(x Ð 10)°
Mathematics Support Materials: Mathematics 3 (Int 2) Ð Student Materials 29