(2^6)^2*(2^2)^7 / (2^4)^6=2^12*2^14 / 2^24= 2^26 / 2^24=2^2=4.
Ответ: 4.
S4=b1*(q^4-1) / q-1
S4=65
65=b1*(-65/81) / (-1/3)
65=65b1 / 27
b1=27
1)x²-49=(x-7)*(x+7)
<span>2)25x<span>²-10xy+y²=(5*x-y)*(5*x-y)</span></span>
<span><span>Прости но с 3 не понятки. </span></span>
18k²+7y-7ky-18k=18k(k-1)-7y(k-1) = (18k-7y)(k-1)
k=1/9, y=2/7
(18·1/9-7·2/7)(1/9-1)=(2-2)(1/9-1)=0
18k²+7-7ky-18k
18·1/9·1/9+7-7·2/7*1/9·-18·1/9=2/9+7-2-2=3_2/9