Page 6 - Grab Me SPM Add Mathematics Form 4,5

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Example 4 Solution

Given the function f(x) = |4x – 3|. (a) (i) f(–2) = |4(–2) – 3|
(a) Find = |–11|
(i) the image of –2, = 11
(ii) the objects of 5, (ii) If f(x) = 5, then |4x – 3| = 5
(iii) the value of x when f(x) = 0. 4x – 3 = 5 or 4x – 3 = –5
(b) (i) Sketch the graph of f(x) for the domain 4 x = 8 4x = –2
–2  x  2. x = 2 x = – 1
(ii) Hence, state the corresponding range. 2
(iii) f(x) = 0
4x – 3 = 0
TIPS x = 3
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f(x) ©PAN ASIA PUBLICATIONS
y
(b) (i)
11
Range  f(x) = |4x – 3|
5
3
0  x –2 0 3 2 x
Domain –
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(ii) The range of f is 0  f(x)  11.

Ch 1_Grab Me SPM AddMaths F4.indd 4 13/05/2022 8:56 AM