Question

Determina numerele naturale de forma ab stiind ca : aba+bab=777 (cu linie deasupra)

Answer 1

Răspuns:

aba+bab=777

100a+10b+a+100b+10a+b=777

111a+111b=777

111(a+b)=777

a+b=7

a∈{1, 2, 3, 4, 5, 6}

b∈{6, 5, 4, 3, 2, 1}

=> ab∈{16, 25, 34, 43, 52, 61}