Page 35 - Mathematics

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The inequality x > means that there are infinitely many real numbers satisfying
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this condition. Thus, they can be represented on a number line by using an arrow
1
with a small circle at (initial point) since it is not included in the set.
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1 Tanzania Institute of Education
The following number line shows all the real numbers which are greater than .

1 2
x >
2

1
-1 0 2 1

Note:

1. A small circle (0) indicates that the number in a given set of real numbers
is excluded in the given set. This is always true for a set of real numbers

which involve < or > inequality symbols.
2. A thick dot (• ) indicates that the number in a given set of numbers is
included in the given set. This is always true for set of real numbers which

involve or ≤ ≥ inequality symbols.

Example 2.16

Use a number line to represent all real numbers x in each of the following:
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1
(a) − ≤< (c) −<≤
2
x
x
2
2 3
3
(b) x ≤ (d) x ≤ 3 or x ≥ 3
2
Solution
1 x <2
Mathematics Form One
2
(a)

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25/10/2024 09:51:09
Mathematics form 1.indd 29
Mathematics form 1.indd 29 25/10/2024 09:51:09