Question

Determinati toate numerele naturale de forma
x2
2y
1x9
y19

Answer 1

x2....x={1,2,3,4,5,6,7,8,9}
2y....y={0,1,2,3,4,5,6,7,8,9}
1x9.....x={0,1,2,3,4,5,6,7,8,9}
y19....y={1,2,3,4,5,6,7,8,9}