1)9х-1, 2)51,3)а9,5)у(а+с),6)ас+аd-bc-bd,7)(x+y)(a-b),8)x=0,10)-113
<span>b3 + b4 = b2*q + b2*q^2 = b2 * (q + q^2) = 36 </span>
<span>Вместо b2 подставляем его численное значение и решаем </span>
<span>81 * (q + q^2) = 36 </span>
<span>9q^2 + 9q - 4 = 0 </span>
<span>q = 1/3 </span>
<span>b1 = b2 / q = 81 / (1/3) = 243 </span>
<span>b5 = b2 * q^3 = 81 * (1/27) = 3 </span>
<span>b1 - b3 = 243 - 3 = 240</span>