Question

Deteminati elementele multimilor :C=(xEZ/10 supra 2x + 1 EZ )

Answer 1

10/(2x+1)€Z
=>(2x+1)€D10 ; D10€Z
D10={-10;-5;-1;1;5;10}
=>(2x+1)€{-10;-5;-1;1;5;10}
=>2x€{-10-1; -5-1; -1-1; 1-1; 5-1; 10-1}
=>2x€{-11; -6; -2; 0; 4; 9}

=>x€{-5,5; -3; -1; 0; 2; 4,5}
x€Z
=>C={-3; -1; 0; 2}

Answer 2

2x+1 E Divizorilor lui 10
2x+1 € {1,2,5,10}/-1
2x € {0,1,4,9}
X€{0,2,4.5,0.5}