Question

Determinati elementele multimii: A={x ∈ Z*| |x²-1|(9-|2x+5|)>0}

Answer 1

x≠1 si x≠-1 ca sa nu fie 0 expresia

9>|2x=5|

|2x+5|<9

-9<2x+5<9 |scade, 5 de  peste tot

-14<2x<4 |impartim prin 2>0, ineg.se pastreaza

-7<x<2

x∈(-7;2)\{-1;1} ⇔ x∈(-7;-1)∪(-1;1)∪(1;2)