Question

Determinați numerele de forma x2y (cu bara deasupra) divizibile cu 9 unde x este diferit de y

Answer 1

X apartine {1,2,3,4,5,6,7,8,9} Y apartine {1,3,9} X3Y apartine { 121,123,129,221,223,229,321,323,329,421,423,429,521,523,529,621,623,629,721,723,729,821,823,829,921,923,929}