Determinati toate numerele ab,stiind ca a4b>846

Răspuns :

a4b>846
a={8,9}
pt a=8 => b={7,8,9}
a4b={847; 848; 849}
ab={87; 88; 89}

pt a=9 => b={0,1,2,3,....9}
a4b={940,941,942,943.......949}
ab={90,91,92...  99}

ab={87,88,89,90,.........,99}