Page 58 - 新思维数学学生用书7 样章

2.6 Inequalities

6 For each of these inequalities:

a y > 4 b y > −7 c y > 2.5
i Write down the smallest integer that y could be.
ii Write a list of the integer values that y could be.
7 For each of these inequalities:
a n < −6 b n < 12 c n < 4.5

i Write down the largest integer that n could be.
ii Write a list of the integer values that n could be.

Think like a mathematician

8 Refer back to questions 6 and 7. Discuss the answers to these questions with a
partner.
a In Question 6, why can’t you write down the largest integer that y could be?

b In Question 7, why can’t you write down the smallest integer that n could be?

9 Arun is considering the following problem.
Match each inequality on the left to the correct largest or smallest

integer in the middle, and to the correct list of integers on the right.
The first one has been done for you.

Inequality Largest or smallest integer List of integers

a x > 5.2 A The largest integer is −4. i 5, 4, 3, 2, 1, ...

b y < 5.2 B The smallest integer is 0. ii 6, 7, 8, 9, 10, ...

c m < −3.5 C The smallest integer is 6. iii 0, −1, −2, −3, −4, ...

d p > −3.5 D The smallest integer is −3. iv −4, −5, −6, −7, −8, ...

e k < 0.9 E The largest integer is 5. v 0, 1, 2, 3, 4, ...

f h > −0.9 F Largest integer is 0. vi −3, −2, −1, 0, 1, ...

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