Question

c= x€Nl x-3=8 sau 2x +2 = 18 say x+1<6
Urgent dau coroana

Answer 1

C= {x€N l x-3=8 sau 2x +2 = 18 sau x+1<6}

x-3=8      => x=11

2x+2=18 => x=8

x+1<6     =>x={0, 1, 2, 3, 4}

deci, C={0, 1, 2, 3, 4, 8, 11}