Question

CALCULATI:

A={x ∈ z/ 6 supra 2x-1 ∈ z }

B={x∈ n/ 12 supra 4-x ∈ n}

C={2x-3/ 5 supra 2x-3 ∈ n}

D={ 4 supra x-1 / x∈ Z si 4 supra x-1 ∈ Z}

Answer 1

6/(2x-1) ∈ Z ⇔  (2x-1) ∈ D6    (2x-1) ∈ {-6,-3, -2, -1, 1,2,3,6}
2x ∈ {-5, -2, 0, 2,3,4,7} ⇒  A = {-1, 0, 1, 2}}
12/(4-x) ∈ N ⇔ (4-x) ∈ D12    (4-x) ∈ {-12, -6, -4, -3, -1, 1,2,3,4,6,12}
x ∈ { 16, 10, 8, 7, 5, 3, 2, 0, -2, -8}    B = {16, 10, 8, 7, 5, 3, 2,0} 
5/(2x-3) ∈ N   ⇔ (2x-3) ∈ D5  (2x-3) ∈ {-5, -1, 1, 5}    C = {1,5} 
4/(x-1) ∈ Z ⇔ (x-1) ∈ D4\1     (x - 1) ∈ {-4, -2, -1,  2, 4}    D = {-1, -2, -4, 2,1}