Question

fie A={x apartine lui Z ||x+2|

Answer 1

$x \in Z \\ |x-2| \leq 9 \\ Cazul\ 1:\ x \geq 2 \\ Inecuatia\ devine: \\ x-2 \leq 9 \\ x\ \in \{2, 3, 4, 5, 6, 7, 8, 9, 10, 11\} \\ Cazul\ 2:\ x\ \textless \ 2 \\ Inecuatia\ devine: \\ x-2 \geq -9 \\ x\ \in\ \{-7, -6, -5, -4, -3, -2, -1, 0, 1\} \\ A=\{-7,-6,-5,-4,-3,-2,-1,0,1,2,3,4,5,6,7,8,9,10,11\} \\ card(A)=19$