Question

1) DETERMINATI A U B, A INTERSECTIA B, A\B SI B\A:
D)A={X APROSIMAT N/5X-1<=24};B={X APROSIMAT N*/3X+1<=7
2)A={N APROSIMAT N/N<=7}: B={N APROSIMAT N*/ N ESTE CIFRA PARA.

Answer 1

1) A={x∈N/ 5x-1≤24} ⇒5x≤25 ⇒ x≤5 ⇒ A={0,1,2,3,4,5}
B={x∈N*/ 3x+1≤7} ⇒ 3x≤6 ⇒ x≤2 ⇒ B={1,2}
A∪B={0,1,2,3,4,5}
A∩B={1,2}
A/B={0,3,4,5}
B/A=∅

2)  A={n ∈ N/ n≤7} ⇒ A= {0,1,2,3,4,5,6,7}
 B={n ∈ N*/ n este cifra para} ⇒ B={2,4,6,8,10,12,14,16,...}
A∪B={0,1,2,3,4,5,6,7,8,10,12,14,16,...}
A∩B={2,4,6}
A/B={0,1,3,5,7}
B/A={8,10,12,14,16,...}