Найдите количество n членов прогрессии, в какой b1 = 3/2, bn = 768, sn = 1534,5. (, ).

Sn = b1*(1-q^n)/(1-q) = (b1 - bn*q)(1-q);Sn * (1-q) = (b1 - bn*q)Sn - Sn*q = b1 - bn*qSn - b1 = Sn*q - bn*qSn - b1 = q * (Sn - bn)q = (Sn - b1)/(Sn - bn) = (1534,5 - 1,5)/(1534,5 - 768) = 2bn = b1 * q^(n-1)768 = 1,5 * 2^(n-1)512 = 2^(n-1)2^9 = 2^(n-1)n = 10