Question

Sa se det elem. multimii :
A={ X ∈ N | | 2x-1 |<1 -sau egal-}

Answer 1

$|2x-1| \leq 1 \Rightarrow ~ -1\leq 2x-1 \leq 1. \\ \\ -1 \leq 2x-1 \leq 1 ~~~~~~~~~~~~~~~|+1 \\ \\ 0 \leq 2x \leq 2~~~~~~~~~~~~~~~~~~~~~~~|:2 \\ \\ 0 \leq x \leq 1,~dar~x \in Z \Rightarrow x \in \{0,1\}. \\ \\ A=\{0;1\}.$