Determinati multimile:
b)B={x∈N/10 divizibil (x-2)];
c)C={x∈N/(x-3) divide 4};
d)D={x∈N/(x+3) divide 15};
e)E={x∈N/(2x+1)∈ D15}.
Va rog frumos vreau rezolvarea la toate!

b) B={x∈N/10 divizibil (x-2)];

10 : x- 2 ⇒ x- 2= 1 x- 2= 2    x -2= 5 x- 2=10
x =1+ 2 x = 2+2 x = 5+2 x = 10 +2
x = 3 x = 4 x = 7 x = 12
B= { 3: 4: 7: 12}

c)C={x∈N/(x-3) divide 4};

x- 3I 4    x- 3= 1    x- 3= 2   x- 3= 4
x = 3+1   x = 2+ 3    x = 4+ 3
x = 4 x = 5   x = 7

C= {4: 5:7.}

d)D={x∈N/(x+3) divide 15};

(x+3) I 15 x+ 3= 1 x+3= 3    x+ 3= 5 x+ 3= 15
x = 1+ 3 x = 3+ 3 x = 5+ 3 x = 15+ 3
x = 4 x = 6 x = 8 x = 18
C= {4: 6: 8: 10}

e)E={x∈N/(2x+1)∈ D15}.

2x+1)∈ D15 D₁₅ = { 1: 3: 5: 15}

2x+ 1= 1 2x+ 1= 3 2x+ 1= 5 2x+ 1= 15
2x =1- 1   2x = 3-1 2x = 5- 1   2x = 15- 1
2x = 0 I 2 2x = 2 I2 2x = 4I 2 2x = 14I 2
x = 0 x = 1 x = 2 x = 7

D= { 0: 1: 2: 7.}