b₁q⁶ - b₁q³ = 513
64(q⁶ - q³) = 513
q³(q³ - 1) = 513/64
a(a - 1) = 513/64; a > 0
a² - a - 513/64 = 0
D = 1 + 513/16 = 529/16
a = (1 + 23/4)/2 = 27/8
q³ = a = 27/8
q = 3/2
ответ: 1,5
b₁q⁶ - b₁q³ = 513
64(q⁶ - q³) = 513
q³(q³ - 1) = 513/64
a(a - 1) = 513/64; a > 0
a² - a - 513/64 = 0
D = 1 + 513/16 = 529/16
a = (1 + 23/4)/2 = 27/8
q³ = a = 27/8
q = 3/2
ответ: 1,5