Răspuns:
32/81
Explicație pas cu pas:
1 - (7/9)¹⁷ : [(7/9)·(7/9)⁴]³ = ?
1 - (7/9)¹⁷ : [(7/9)·(7/9)⁴]³ = 1 - (7/9)¹⁷ : [(7/9)¹⁺⁴]³ =
= 1 - (7/9)¹⁷ : [(7/9)⁵]³ = 1 - (7/9)¹⁷ : (7/9)⁵ˣ³ =
= 1 - (7/9)¹⁷ : (7/9)¹⁵ = 1 - (7/9)¹⁷⁻¹⁵ = 1 - (7/9)² =
= ⁸¹⁾1 - 49/81 = (81-49)/81 = 32/81