Question

 Care din urmatoarele multimi reprezinta intervale : 
 A= { x  ∈ R | - 1 ≤ x ≤ 2 } 
B = { x ∈ R | 0 mai mic x ≤ 1,5 }
C = {x ∈ R | x ≥ 4 } 

Answer 1

-1≤x≤2⇒x∈[-1,2] deci A={-1,0,1,2]
0<x≤1,5⇒x∈(0,1,5] deci B={1; 1,1 ; 1,2 ;1,3 ;1,4 ;1,5 }
x≥4⇒x∈[4,+infinit) deci C={4,5,6,7,8,9,10....}