Răspuns :
18:(x+1)
expresia x+1 poate fi
x+1=2 deci x=1
x+1=3 deci x=2
x+1=6 deci x=5
x+1=9 deci x=8
x+1=18 deci x=17
multimea eate {1,2,5,8,17}
expresia x+1 poate fi
x+1=2 deci x=1
x+1=3 deci x=2
x+1=6 deci x=5
x+1=9 deci x=8
x+1=18 deci x=17
multimea eate {1,2,5,8,17}
18÷[1+1]=18÷2=9
18÷[2+1]=18÷3=6
18÷[3+1]=18÷4= nu merge x=4 nu merge
18÷[5+1]=18÷6=3 x=6 sau 7 nu merge
18÷[8+1]=18÷9=2
18÷[17+1]=18÷18=1
{9;6;3;2;1}
18÷[2+1]=18÷3=6
18÷[3+1]=18÷4= nu merge x=4 nu merge
18÷[5+1]=18÷6=3 x=6 sau 7 nu merge
18÷[8+1]=18÷9=2
18÷[17+1]=18÷18=1
{9;6;3;2;1}