1/a/ 3 puisque 3x3 = 9
b/ 49 puisque 7x7 = 49
3/ A = 2 B = 1/2 (A + 2/A) = 1/2 (2 + 1) = 3/2 ,C = 1/2 (B + 2/B) = 1/2 (3/2 + 2/(3/2)) = 15/12 ,D = 1/2 (C + 2/C) = 1/2 (15/12 + 2/(15/12)) = 513/360 .E = 1/2 (D + 2/D) = 1/2 (513/360 + 2/(513/360)) = 522369/369360 ≈ 1,414254donc E² ≈ 2,000114 ≈ 2