Răspuns:
Explicație pas cu pas:
0,(4) = 4/9
0,(7) = 7/9
7,(3) = (73-7)/9 = 66/9 = 22/3
1,8(3) = (183-18)/90 = 165/90 = 55/30 = 11/6
0,2(6) = (26-2)/90 = 24/90 = 8/30 = 4/15
[0,(4)]² = (4/9)² = 16/81 = 0,(197530864)
[0,(7)]² = (7/9)² = 49/81 = 0,(604938271)
[7,(3)]² = (22/3)² = 484/9 = 53,(7)
[1,8(3)]² = (11/6)² = 121/36 = 3,36(1)
[0,2(6)]² = (4/15)² = 16/225 = 0,07(1)