Răspunsuri

2014-10-01T09:02:07+03:00
A+b ∈{1,2,3,4,}⇒a ∈{1,2,3,4} 
b∈{3,2,1,0}
ab1∈{131,121,111,101,211,201,221,311,301,401}

Ne gandim la numerele care adunate sa fie mai mici ca 5