Page 6 - Top Class Additional Mathematics Tg 4

Additional Mathematics Form 4 Chapter 1 Functions

7. Sketch the graphs of the following functions f(x) for the given domains. Then, state the ranges. PL 3
Lakar graf bagi fungsi f(x) berikut untuk domain yang diberikan. Seterusnya, nyatakan julatnya.
Example (a) f(x) = x – 3, –2 < x < 4

f(x) = 1 – 4x, –1 < x < 3
x –2 0 3 4
1
x –1 0 3 f(x) 5 3 0 1
4
f(x) 5 1 0 11
f(x)
f(x) 5
11 3
5 1
x
1 x –2 0 3 4
–1 0 1 3
–
4
The range is 0 < f(x) < 5.
The range is 0 < f(x) < 11.

(b) f(x) = 2x + 6, –4 < x < 1 (c) f(x) = 5x – 4, –3 < x < 2

4
x –4 –3 0 1 x –3 0 5 2
f(x) 2 0 6 8 f(x) 19 4 0 6

f(x)
f(x)
8 19
6

2 6
4
x x
–4 –3 0 1 –3 0 4 2
–
5
The range is 0 < f(x) < 8.
The range is 0 < f(x) < 19.

8. Solve each of the following problems. PL 4
Selesaikan setiap masalah berikut.
Example
A function is defined by f : x → x – 8. Find
Suatu fungsi ditakrifkan oleh f : x → x – 8. Cari
(i) f(–3)
(ii) the value of x if f(x) = –5.
nilai x jika f(x) = –5.

(i) f(x) = x – 8 (ii) f(x) = –5
f(–3) = –3 – 8 x – 8 = –5
= –11 x = 3

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