Question

Fie A={-3, -2, -1 , 0, 3, 4, 5, 9}. Determinati multimea A∩S, unde S este multimea solutiilor pt fiecare dintre inecuatiile urmat, rezolvate in multimea numerelor intregi:
a)x+2>5
b)5x+7≤2

Answer 1

a) x+2 > 5
x > 3
S = {4, 5, 6, 7,....}
$A\cap S=\{4,5\}$

b)
$5x+7\leq2$
5x+7 < 3
5x < -4
x < -0,8
$x\leq-1$
S = {-1, -2, -3,....}
$A\cap S=\{-1,-2,-3\}$