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The second volume of junior one mathematics textbook
( 1)2x- 1 & gt; 0

2x & gt 1

x & gt 1/2

x+ 1 & lt; three

x & lt2

∴ 1/2<; x & lt2

(2)-3x- 1 & gt; three

3x+ 1 & lt; -3

x & lt-4/3

2x+ 1 & gt; three

2x & gt3- 1

x & gt 1

Without common parts, there is no solution.

(3)3(x- 1)+ 13 >; 5x-2 (5x)

3x-3+ 13 >5x- 10+2x

3x+ 10 >7x- 10

4x & lt20

X< five

5-(2x+ 1)& lt; 3-6 times

5-2x- 1 & lt; 3-6 times

6x-2x & lt; 3-5+ 1

4x & lt- 1

x & lt- 1/4

∴x<; - 1/4

⑷x-3(x-2)≥4

x-3x+6≥4

-2x≥-2

x≤ 1

(2) Multiply both sides of the equation by 3.

1+2x & gt; 3(x- 1)

1+2x & gt; 3x-3

2x-3x >-3- 1

X< iv

∴x≤ 1

(5) x-3(x-2)≥4

x-3x+6≥4

-2x≥4-6

x≤ 1

② Multiply both sides of the equation by 10.

2(2x- 1)>5(x+ 1)

4x-2 & gt; 5x+5

4x-5x & gt; 5+2

x & lt-7

∴x<; -7

(6) Multiply both sides of (1) equation by 2 to obtain

x+4 & lt; 2*2

x & lt0

(2) Multiply both sides of the equation by 6.

3(x+2)>2(x+3)

3x+6 >2x+6

x & gt0

Without common parts, there is no solution.