Question

C.m.m.d.c al nr. 54, 63, 72 ??

Answer 1

54=2·3³
63=3²·7
72=2³·3²  ⇒(54,63,72)=3²=9

Answer 2

$54=2*3*3*3=2* 3^{3} \\ 63=3*3*7= 3^{2}*7 \\ 72=2*2*2*3*3= 2^{3}* 3^{2} \\ ....................................................... \\ C.m.m.d.c(54;63;72):3*3= 3^{2}=\boxed{9}$