Răspuns:
a³=(∛(9+10/3*√71/3))³=9+10/3*√71/3
b³=(∛(9-10/3*√71/3))³=9-10/3*√71/3
a³+b³=9+10/3*√71/3+9-10/3*√71/3=18
Explicație pas cu pas:
