Question

Please solve this problem because tomorrow is my exam.​

Answer 1

Step-by-step explanation:

a). A = {x  ∈ R  I  5x-8 < 7}

5x - 8 < 7 <=> 5x < 8+7  <=> 5x < 15  =>

x < 3  => A = (-∞ ; 3)

A ∩ N = {0 ; 1 ; 2}

A - N* = (-∞ ; 3) - {1 ; 2}

b).  A = { x ∈ R  I  7x+2 ≤ 9}

7x+2 ≤ 9 <=> 7x ≤ 7  => x ≤ 1 => x ∈ (-∞ ; 1]

A ∩ N = {0 ; 1}

A-N* = (-∞ ; 1)

c). A = { x ∈ R  I  I 2x-1 I < 5}

I 2x-1 I < 5  <=> -5 ≤ 2x-1 ≤ 5  <=>

-4 ≤ 2x ≤ 6  <=> -2 ≤ x ≤ 3  => x ∈ [-2 ; 3]

A ∩ N = {0 ; 1 ; 2 ; 3}

A - N* = [-2 ; 3) - {1 ; 2}

d). A = {x ∈ R I I 6-3x I ≤ 9}

I 6-3x I ≤ 9  <=> -9 ≤ 6-3x ≤ 9  <=>

-15 ≤ -3x ≤ 3 <=> -5 ≤ -x ≤ 3  =>

-3 ≤ x ≤ 5  => x ∈ [-3 ; 5]

A ∩ N = {0 ; 1 ; 2 ; 3 ; 4 ; 5}

A - N* = [-3 ; 5) - {1 ; 2 ; 3 ; 4}