Question

Rezolvati in multimea nr.nat. ecuatiile a) (x+1) (y+2)=15

Answer 1

Răspuns:

(x;y)∈{(0;13);(2;3);(4;1)}

Explicație pas cu pas:

(x+1) (y+2)=15=1*15=3*5+5*3=15*1

x+1=1....x=0 si y+2=15...y=13

x+1=3...x=2 si y+2=5...y=3

x+1=5....x=4 si y+2=3...y=1

x+1=15 si y+2=1...y=-1∉N

(x;y)∈{(0;13);(2;3);(4;1)}